@article{ke_mehrotra_hopkins_2021, title={3-D Prismatic Packaging Methodologies for Wide Band Gap Power Electronics Modules}, volume={11}, DOI={10.1109/TPEL.2021.3081679}, journal={IEEE TRANSACTIONS ON POWER ELECTRONICS}, author={Ke, Haotao and Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2021}, month={Nov} } @inproceedings{hopkins_yu_mehrotra_cheng_sinha_maru_mescia_2021, title={A 40kV/mm Organic Substrate for Low Voltage Power SiP and >10kV Power Modules}, author={Hopkins, Douglas C. and Yu, Wensong and Mehrotra, Utkarsh and Cheng, Tzu-Hsuan and Sinha, Sourish Sankar and Maru, Karan and Mescia, Nicholas}, year={2021}, month={Mar} } @inproceedings{mehrotra_hopkins_2021, title={A New Cascaded SuperCascode High Voltage Power Switch}, ISBN={9781728189499}, url={http://dx.doi.org/10.1109/apec42165.2021.9487049}, DOI={10.1109/apec42165.2021.9487049}, booktitle={2021 IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2021}, month={Jun} } @inproceedings{maru_hopkins_2021, title={Accessible & Adaptable Approach for Calculating the Thermal Resistance of a Power Package using ParaPower}, author={Maru, Karan and Hopkins, Douglas C.}, year={2021}, month={Mar} } @inproceedings{hopkins_cheng_mehrotra_yu_2021, title={Advanced Dual-Sided Half-bridge Packaging with Epoxy Insulated Metal Substrates (eIMS)}, author={Hopkins, Douglas C. and Cheng, Tzu-Hsuan and Mehrotra, Utkarsh and Yu, Wensong}, year={2021}, month={Jun} } @inproceedings{hopkins_cheng_mehrotra_2021, title={Advances in Highly Thermally Conductive Organic Power Packaging}, author={Hopkins, Douglas C. and Cheng, Tzu-Hsuan and Mehrotra, Utkarsh}, year={2021}, month={Apr} } @article{mehrotra_hopkins_2021, title={Analytical Method to Optimize the Cascaded SuperCascode Power Switch Balancing Network}, DOI={10.1109/WiPDA49284.2021.9645114}, journal={2021 IEEE 8TH WORKSHOP ON WIDE BANDGAP POWER DEVICES AND APPLICATIONS (WIPDA)}, author={Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2021} } @article{mehrotra_ballard_hopkins_2021, title={Bidirectional Solid-State Circuit Breaker using Super Cascode for MV SST and Energy Storage Systems}, ISSN={2168-6777 2168-6785}, url={http://dx.doi.org/10.1109/JESTPE.2021.3081684}, DOI={10.1109/JESTPE.2021.3081684}, journal={IEEE Journal of Emerging and Selected Topics in Power Electronics}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Mehrotra, Utkarsh and Ballard, Bahji and Hopkins, Douglas C.}, year={2021}, pages={1–1} } @article{kanale_narasimhan_cheng_agarwal_shah_baliga_bhattacharya_hopkins_2021, title={Comparison of the Capacitances and Switching Losses of 1.2 kV Common-Source and Common-Drain Bidirectional Switch Topologies}, DOI={10.1109/WiPDA49284.2021.9645130}, journal={2021 IEEE 8TH WORKSHOP ON WIDE BANDGAP POWER DEVICES AND APPLICATIONS (WIPDA)}, author={Kanale, Ajit and Narasimhan, Sneha and Cheng, Tzu-Hsuan and Agarwal, Aditi and Shah, Suyash Sushilkumar and Baliga, B. Jayant and Bhattacharya, Subhashish and Hopkins, Douglas C.}, year={2021} } @inproceedings{mehrotra_morgan_hopkins_2021, title={Design and Characterization of 3.3 kV-15 kV rated DBC Power Modules for Developmental Testing of WBG devices}, ISBN={9781728189499}, url={http://dx.doi.org/10.1109/apec42165.2021.9487311}, DOI={10.1109/apec42165.2021.9487311}, booktitle={2021 IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Mehrotra, Utkarsh and Morgan, Adam J. and Hopkins, Douglas C.}, year={2021}, month={Jun} } @inproceedings{sinha_hopkins_2021, title={E-Field Reduction Techniques in HV Multi-layered Modules Using New Capacitive Modelling Method}, author={Sinha, Sourish S. and Hopkins, Douglas C.}, year={2021}, month={Mar} } @inproceedings{shah_bhattacharya_kanale_cheng_mehrotra_agarwal_baliga_hopkins_2021, title={Optimized AC/DC Dual Active Bridge Converter using Monolithic SiC Bidirectional FET (BiDFET) for PV Applications}, author={Shah, Suyash Sushilkumar and Bhattacharya, Subhashish and Kanale, Ajit and Cheng, Tzu-Hsuan and Mehrotra, Utkarsh and Agarwal, Aditi and Baliga, B.Jayant and Hopkins, Douglas C.}, year={2021}, month={Oct} } @article{shah_narwal_bhattacharya_kanale_cheng_mehrotra_agarwal_baliga_hopkins_2021, title={Optimized AC/DC Dual Active Bridge Converter using Monolithic SiC Bidirectional FET (BiDFET) for Solar PV Applications}, DOI={10.1109/ECCE47101.2021.9595533}, journal={2021 IEEE ENERGY CONVERSION CONGRESS AND EXPOSITION (ECCE)}, author={Shah, Suyash Sushilkumar and Narwal, Ramandeep and Bhattacharya, Subhashish and Kanale, Ajit and Cheng, Tzu-Hsuan and Mehrotra, Utkarsh and Agarwal, Aditi and Baliga, B. Jayant and Hopkins, Douglas C.}, year={2021} } @inproceedings{mehrotra_hopkins_2021, title={Scalable Cascaded SuperCascode High Voltage Power Switch}, author={Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2021}, month={Mar} } @inproceedings{mehrotra_morgan_mckeown_hopkins_2021, title={Study of Al wire bonds to understand cross-talk and current carrying capacity in WBG Power Module Design}, author={Mehrotra, Utkarsh and Morgan, Adam J. and McKeown, Michael and Hopkins, Douglas C.}, year={2021}, month={Apr} } @inproceedings{kanale_cheng_shah_han_agarwal_baliga_hopkins_bhattacharya_2021, title={Switching Characteristics of a 1.2 kV, 50 mΩ SiC Monolithic Bidirectional Field Effect Transistor (BiDFET) with Integrated JBS Diodes}, ISBN={9781728189499}, url={http://dx.doi.org/10.1109/apec42165.2021.9487410}, DOI={10.1109/apec42165.2021.9487410}, booktitle={2021 IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Kanale, Ajit and Cheng, Tzu-Hsuan and Shah, Suyash Sushilkumar and Han, Kijeong and Agarwal, Aditi and Baliga, B. Jayant and Hopkins, Douglas and Bhattacharya, Subhashish}, year={2021}, month={Jun} } @inproceedings{cheng_hopkins_2021, title={Thermal Performance Comparison of DBC and ERCD for Single- and Double-Sided Power Modules}, author={Cheng, Tzu-Hsuan and Hopkins, Douglas C}, year={2021}, month={Apr} } @article{cheng_nishiguchi_fukawa_baliga_bhattacharya_hopkins_2020, title={Characterization of Highly Thermally Conductive Organic Substrates for a Double-Sided Cooled Power Module}, volume={2020}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/2380-4505-2020.1.000277}, DOI={10.4071/2380-4505-2020.1.000277}, abstractNote={Abstract Silicon-Carbide (SiC) power devices have become a promising option for traditional Silicon (Si) due to the superior material properties. To fully take advantage of the SiC devices, a high-performance power device packaging solution is necessary. This study proposes a cost-effective double-sided cooled (DSC) 1.2 kV SiC half-bridge power module using organic epoxy-resin composite dielectric (ERCD) substrates. The high mechanical and thermal performance of the power module is achieved by the low-modulus, moderate thermal conductivity, and relatively thin (120 μm) layer of ERCD material compared with traditional metal-clad ceramic approaches. This novel organic dielectric can withstand high voltage (5 kV @ 120 μm) and operate up to 250°C continuously, which is indispensable for high power applications. The thermal modeling results show that the equivalent thermal resistance junction-to-case (Rjc_eq) of the DSC power module using dual direct bonded copper (DBC) is 17% higher than the dual ERCD configuration. Furthermore, a non-insulated DSC power module concept is proposed for maximizing thermal performance by considering thermal vias in the ERCD substrate and direct-soldered heat sink. A thought process for optimization of thermal via design is demonstrated and it shows up to 24% of improvement on thermal performance compared with the insulated DSC power module.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Cheng, Tzu-Hsuan and Nishiguchi, Kenji and Fukawa, Yoshi and Baliga, B. Jayant and Bhattacharya, Subhashish and Hopkins, Douglas C.}, year={2020}, month={Sep}, pages={000277–000281} } @misc{hopkins_2020, title={Creating a Fast Turn Lab to Package Developmental Power Devices with a Packaging Example}, author={Hopkins, Douglas C.}, year={2020}, month={Aug} } @inproceedings{cheng_mehrotra_hopkins_2020, title={Development of 3.3 kV-Capable, Open-Source, Low Cost Packaging Solution for Sic Transistor and Diode Testing}, author={Cheng, Tzu-Hsuan and Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2020}, month={Feb} } @inproceedings{murthy_mehrotra_yu_hopkins_2020, title={Dynamic and Thermal IOL Test Systems for 3.3kV-6.5kV Die Development}, author={Murthy, Pranav and Mehrotra, Utkarsh and Yu, Wensong and Hopkins, Douglas C.}, year={2020}, month={Feb} } @inproceedings{mehrotra_ballard_hopkins_2020, title={High Current Medium Voltage Bidirectional Solid State Circuit Breaker using SiC JFET Super Cascode}, ISBN={9781728158266}, url={http://dx.doi.org/10.1109/ecce44975.2020.9236347}, DOI={10.1109/ecce44975.2020.9236347}, booktitle={2020 IEEE Energy Conversion Congress and Exposition (ECCE)}, publisher={IEEE}, author={Mehrotra, Utkarsh and Ballard, Bahji and Hopkins, Douglas C.}, year={2020}, month={Oct} } @article{mehrotra_brazzle_mckeown_hopkins_2020, title={Lithium Battery Cell Level Fusing with Aluminum Heavy Wire Bonds}, volume={2020}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/2380-4505-2020.1.000009}, DOI={10.4071/2380-4505-2020.1.000009}, abstractNote={Abstract Aluminum heavy wire bonds interconnects are a potential alternative to laser or resistance welded bus bars due to its ease of manufacturability, long term reliability and low cost for battery banks. They can also be utilized as a fault protection solution in case of a surge current, dead short, etc, and to isolate a bad cell preventing synchronous failure. Typically, the current-carrying capability of a wire is estimated using standard data generated by testing in free air. However, a deviation in the capacity limits can occur due to the proximity of interconnect to larger thermal masses and different heat extraction techniques found in present day lithium battery packs; e.g., fluid channel cooling, encapsulated wires, etc. The cylindrical cell cathode, anode, and the busbar material constitute a large thermal mass to increase the fusing current in wire bonds above conventional levels. To better predict and design the interconnects advanced and system-specific models should be developed. This paper presents a new mathematical approach which includes the effect of convective cooling inside the battery pack to do an early step estimation of the current handling capacity and fusing time of different diameter wires. The paper also presents a finite element model that includes the impact of boundary conditions, wire length and wire diameter on steady-state current handling capacity of 99.99 % Al wire. Both steady-state and transient simulations were performed to estimate fusing times at different time rated conditions. The paper concludes by providing new curve-fit patterns to give future battery pack designers further insight aiding new designs.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Mehrotra, Utkarsh and Brazzle, Arthur and McKeown, Michael and Hopkins, Douglas C.}, year={2020}, month={Sep}, pages={000009–000014} } @inproceedings{mehrotra_ballard_cheng_baliga_bhattacharya_hopkins_2020, title={Optimized Highly Efficient SSCB Using Organic Substrate Packaging for Electric Vehicle Applications}, ISBN={9781728146294}, url={http://dx.doi.org/10.1109/itec48692.2020.9161539}, DOI={10.1109/itec48692.2020.9161539}, booktitle={2020 IEEE Transportation Electrification Conference & Expo (ITEC)}, publisher={IEEE}, author={Mehrotra, Utkarsh and Ballard, Bahji and Cheng, Tzu-Hsuan and Baliga, B. Jayant and Bhattacharya, Subhashish and Hopkins, Douglas C.}, year={2020}, month={Jun} } @inproceedings{mehrotra_cheng_kanale_agarwal_han_baliga_bhattacharya_hopkins_2020, title={Packaging Development for a 1200V SiC BiDFET Switch Using Highly Thermally Conductive Organic Epoxy Laminate}, ISBN={9781728148366}, url={http://dx.doi.org/10.1109/ispsd46842.2020.9170116}, DOI={10.1109/ispsd46842.2020.9170116}, booktitle={2020 32nd International Symposium on Power Semiconductor Devices and ICs (ISPSD)}, publisher={IEEE}, author={Mehrotra, Utkarsh and Cheng, Tzu-Hsuan and Kanale, Ajit and Agarwal, Aditi and Han, Kijeong and Baliga, B. Jayant and Bhattacharya, Subhashish and Hopkins, Douglas C.}, year={2020}, month={Sep} } @misc{sinha_hopkins_2020, title={ParaPower – Leveraging Finite Difference Simulator for Quick Thermal Design}, author={Sinha, Sourish Sankar and Hopkins, Douglas C.}, year={2020}, month={Jan} } @inproceedings{mehrotra_morgan_hopkins_2020, title={Traditional DBC-Based Power Modules for Test in Developing 3.3kV-15kV WBG Devices}, author={Mehrotra, Utkarsh and Morgan, Adam and Hopkins, Douglas C.}, year={2020}, month={Feb} } @inproceedings{hopkins_cheng_mehrotra_2020, title={Ultra-High Density Double-Sided Half Bridge Packaging}, author={Hopkins, Douglas C. and Cheng, Tzu-Hsuan and Mehrotra, Utkarsh}, year={2020}, month={Jul} } @inproceedings{kanale_cheng_hanl_baliga_bhattacharya_hopkins_2019, title={1.2 kV, 10 A, 4H-SiC Bi-Directional Field Effect Transistor (BiDFET) with Low On-State Voltage Drop}, author={Kanale, Ajit and Cheng, Tzu-Hsuan and Hanl, Kijeong and Baliga, B. Jayant and Bhattacharya, Subhashish and Hopkins, Douglas}, year={2019}, month={Sep} } @inproceedings{gao_mehrotra_hopkins_2019, title={A High-Bandwidth Resistive Current Sensing Technology for Breakers and Desaturation Protection}, ISBN={9781728137612}, url={http://dx.doi.org/10.1109/wipda46397.2019.8998767}, DOI={10.1109/wipda46397.2019.8998767}, booktitle={2019 IEEE 7th Workshop on Wide Bandgap Power Devices and Applications (WiPDA)}, publisher={IEEE}, author={Gao, Bo and Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2019}, month={Oct} } @inproceedings{hopkins_cheng_gao_boteler_2019, title={Advances in Organic Substrate Approaches for High Voltage Power Electronics Packaging}, author={Hopkins, Douglas C. and Cheng, Tzu-Hsuan and Gao, Bo and Boteler, Lauren}, year={2019}, month={Oct} } @inproceedings{cheng_gao_boteler_hopkins_2019, title={Advances in Organic Substrate Approaches for High Voltage Power Electronics Packaging}, author={Cheng, Tzu-Hsuan and Gao, Bo and Boteler, Lauren and Hopkins, Douglas}, year={2019}, month={Nov} } @inproceedings{ballard_mehrotra_hopkins_2019, title={Bi–Directional Solid-State Circuit Breaker for MV Applications Based on SuperCascode Switching}, author={Ballard, Bahji and Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2019}, month={Feb} } @inproceedings{cheng_gao_nishiguchi_hopkins_2019, title={Characterization of a Topside Cooled Epoxy-Resin Composite Dielectric (ERCD) Package for Bi-Directional Power Switch}, author={Cheng, Tzu-Hsuan and Gao, Bo and Nishiguchi, Kenji and Hopkins, Douglas}, year={2019}, month={Oct} } @inproceedings{hopkins_ballard_mehrotra_2019, title={Design and Integration of WBG Solid State Circuit Protection}, author={Hopkins, Douglas C. and Ballard, Bahji and Mehrotra, Utkarsh}, year={2019}, month={Mar} } @inproceedings{ballard_mehrotra_hopkins_2019, title={Designing for Switching Stresses in a Circuit Breaker Application using SiC Semiconductors}, author={Ballard, Bahji and Mehrotra, Utkarsh and Hopkins, Douglas C.}, year={2019}, month={Oct} } @inproceedings{guven_gao_hopkins_2019, title={Development of a High Frequency LLC Resonant Converter for Investigation of MLCCs for EV applications}, author={Guven, Musab and Gao, Bo and Hopkins, Douglas C.}, year={2019}, month={Aug} } @inproceedings{sinha_ballard_hopkins_2019, title={ERCD Power Stage Characterization for MV SSCB Application}, author={Sinha, Sourish S. and Ballard, Bahji and Hopkins, Douglas C.}, year={2019}, month={Aug} } @book{kulick_hopkins_2019, title={Edge Interconnect Packaging of Integrated Circuits for Power Systems}, number={10,325,875B2}, author={Kulick, Jason M. and Hopkins, Douglas}, year={2019}, month={Jun} } @inproceedings{morgan_gao_hopkins_2019, title={High Frequency Self-Oscillating WBG-based Power Conversion}, author={Morgan, Adam and Gao, Bo and Hopkins, Douglas C.}, year={2019}, month={Apr} } @inproceedings{morgan_kanale_han_baliga_hopkins_2019, title={New Dynamic Power MOSFET Model to Determine Maximum Device Operating Frequency}, ISBN={9781538683309}, url={http://dx.doi.org/10.1109/APEC.2019.8722197}, DOI={10.1109/APEC.2019.8722197}, booktitle={2019 IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Morgan, Adam J. and Kanale, Ajit and Han, Kijeong and Baliga, Jayant and Hopkins, Douglas C.}, year={2019}, month={Mar} } @inproceedings{morgan_kanale_han_baliga_hopkins_2019, title={New Dynamic Power MOSFET Model to Determine Maximum Device Operating Frequency}, author={Morgan, Adam and Kanale, Ajit and Han, Kijeong and Baliga, Jayant and Hopkins, Douglas C.}, year={2019}, month={Apr} } @inproceedings{hopkins_ballard_2019, title={Opportunities in Power Applications using Epoxy Resin Composite Dielectrics}, author={Hopkins, Douglas and Ballard, Bahji}, year={2019}, month={Aug} } @inproceedings{hopkins_2019, title={Power Packaging Assembly Challenges}, author={Hopkins, Douglas C.}, year={2019}, month={Mar} } @inproceedings{jorgensen_cheng_hopkins_beczkowski_uhrenfeldt_munk-nielsen_2019, title={Thermal Characteristics and Simulation of an Integrated GaN eHEMT Power Module}, ISBN={9789075815313}, url={http://dx.doi.org/10.23919/epe.2019.8915012}, DOI={10.23919/epe.2019.8915012}, booktitle={2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe)}, publisher={IEEE}, author={Jorgensen, Asger Bjorn and Cheng, Tzu-Hsuan and Hopkins, Douglas and Beczkowski, Szymon and Uhrenfeldt, Christian and Munk-Nielsen, Stig}, year={2019}, month={Sep} } @inproceedings{hopkins_2019, title={Trends in Power Electronics Packaging}, author={Hopkins, Douglas C.}, year={2019}, month={Apr} } @inproceedings{mehrotra_hopkins_2019, title={WBG Solid State Circuit Protection using 10kV/200 A Super Cascode power module}, author={Mehrotra, Utkarsh and Hopkins, Douglas}, year={2019}, month={Aug} } @inproceedings{gao_morgan_xu_zhao_hopkins_2018, title={6.0kV, 100A, 175kHz super cascode power module for medium voltage, high power applications}, DOI={10.1109/apec.2018.8341182}, note={\urlhttps://ieeexplore.ieee.org/document/8341182}, booktitle={Thirty-third annual ieee applied power electronics conference and exposition (apec 2018)}, author={Gao, B. and Morgan, A. J. and Xu, Y. and Zhao, X. and Hopkins, Douglas C}, year={2018}, pages={1288–1293} } @inproceedings{gao_morgan_xu_zhao_ballard_hopkins_2018, title={6.5kV SiC JFET-based Super Cascode Power Module with High Avalanche Energy Handling Capability}, ISBN={9781538659090}, url={http://dx.doi.org/10.1109/wipda.2018.8569146}, DOI={10.1109/wipda.2018.8569146}, booktitle={2018 IEEE 6th Workshop on Wide Bandgap Power Devices and Applications (WiPDA)}, publisher={IEEE}, author={Gao, Bo and Morgan, Adam and Xu, Yang and Zhao, Xin and Ballard, Bahji and Hopkins, Douglas C.}, year={2018}, month={Oct} } @inproceedings{gao_morgan_xu_zhao_hopkins_2018, title={6.5kV, 100A, 175kHz Super Cascode Power Module (SCPM)}, author={Gao, Bo and Morgan, Adam and Xu, Yang and Zhao, Xin and Hopkins, Douglas C.}, year={2018}, month={Feb} } @inproceedings{chen_hopkins_2018, title={Comparing Power Packaging Through A Thermal Resistance Circle Based on Finite Element Analysis}, author={Chen, Timothy and Hopkins, Douglas C.}, year={2018}, month={Feb} } @article{de_morgan_iyer_ke_zhao_vechalapu_bhattacharya_hopkins_2018, title={Design, package, and hardware verification of a high-voltage current switch}, volume={6}, DOI={10.1109/jestpe.2017.2727051}, note={\urlhttps://ieeexplore.ieee.org/document/7981339/}, number={1}, journal={IEEE Journal of Emerging and Selected Topics in Power Electronics}, author={De, A. K. and Morgan, A. J. and Iyer, V. M. and Ke, H. T. and Zhao, X. and Vechalapu, K. and Bhattacharya, Subhashish and Hopkins, Douglas C}, year={2018}, pages={441–450} } @inproceedings{golding_hopkins_2018, title={Development of De-encapsulation Process for WBG Semiconductor Packaging Rework and Failure Analysis}, author={Golding, Caitlin and Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{hopkins_2018, title={Heterogeneous Integration Roadmap Update-integrated power electronics (IPE)}, author={Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{gao_zhao_hopkins_2018, title={Increasing Electrical and Thermal Performances of VRMs by Using Folded Flexible Substrate}, ISBN={9781538660171}, url={http://dx.doi.org/10.1109/3dpeim.2018.8525238}, DOI={10.1109/3dpeim.2018.8525238}, booktitle={2018 Second International Symposium on 3D Power Electronics Integration and Manufacturing (3D-PEIM)}, publisher={IEEE}, author={Gao, Bo and Zhao, Xin and Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{han_kanale_baliga_ballard_morgan_hopkins_2018, title={New Short Circuit Failure Mechanism for 1.2kV 4H-SiC MOSFETs and JBSFETs}, ISBN={9781538659090}, url={http://dx.doi.org/10.1109/wipda.2018.8569178}, DOI={10.1109/wipda.2018.8569178}, booktitle={2018 IEEE 6th Workshop on Wide Bandgap Power Devices and Applications (WiPDA)}, publisher={IEEE}, author={Han, Kijeong and Kanale, Ajit and Baliga, B. J. and Ballard, Bahji and Morgan, Adam and Hopkins, Douglas C.}, year={2018}, month={Oct} } @inproceedings{guven_hopkins_2018, title={Parasitic Integration for 500kHz ZVS DC-DC Converter Using New Polymer Material in IMS Module}, author={Guven, Musab and Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{zhao_gao_zhang_hopkins_huang_2018, title={Performance optimization of A 1.2kV SiC high density half bridge power module in 3D package}, DOI={10.1109/apec.2018.8341179}, note={\urlhttp://xplorestaging.ieee.org/ielx7/8336027/8340970/08341179.pdf?arnumber=8341179 ; \urlhttp://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=8341179}, booktitle={Thirty-third annual ieee applied power electronics conference and exposition (apec 2018)}, author={Zhao, X. and Gao, B. and Zhang, L. Q. and Hopkins, Douglas C and Huang, A. Q.}, year={2018}, pages={1266–1271} } @inproceedings{gao_morgan_hopkins_2018, title={Scalable MV/HV Super Cascode Power Module}, author={Gao, Bo and Morgan, Adam and Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{morgan_hopkins_2018, title={Self-Oscillating WBG-based VHF Power Conversion for FREEDM Applications}, author={Morgan, Adam and Hopkins, Douglas C.}, year={2018}, month={Jun} } @inproceedings{hopkins_2017, title={3D Printing Power Supply in Package Power Supply on Chip versus Discrete Packaging}, author={Hopkins, Douglas C.}, year={2017} } @inproceedings{hopkins_zhao_jagannadham_reainthippayasakul_lanagan_jiang_gao_nishiguchi_fukawa_2017, title={Characterization of Novel Materials for Thin Flexible Power Substrates for High-Density Power Electronics}, author={Hopkins, Douglas C. and Zhao, Xin and Jagannadham, K. and Reainthippayasakul, Wuttichai and Lanagan, Michael T. and Jiang, Yifan and Gao, Bo and Nishiguchi, Kenji and Fukawa, Yoshi}, year={2017}, month={Aug} } @article{morgan_zhao_rouse_hopkins_2017, title={Characterization of Silicone Gel for High Temperature Encapsulation in High Voltage WBG Power Modules}, volume={2017}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2017-wa54_099}, DOI={10.4071/isom-2017-wa54_099}, abstractNote={Abstract One of the most important advantages of wide-bandgap (WBG) devices is high operating temperature (>200°C). Power modules have been recognized as an enabling technology for many industries, such as automotive, deep-well drilling, and on-engine aircraft controls. These applications are all required to operate under some form of extreme environmental conditions. Silicone gels are the most popular solution for the encapsulation of power modules due to mechanical stress relief enabled by a low Young's modulus, electrical isolation achieved due to high dielectric strength, and a dense material structure that protects encapsulated devices against moisture, chemicals, contaminants, etc. Currently, investigations are focused on development of silicone gels with long-term high-temperature operational capability. The target is to elevate the temperature beyond 200°C to bolster adoption of power modules in the aforementioned applications. WACKER has developed silicone gels with ultra-high purity levels of < 2ppm of total residual ions combined with > 200°C thermal stability. In this work, leakage currents through a group of WACKER Chemie encapsulant silicone gels (A, B, C) are measured and compared for an array of test modules after exposure to a 12kV voltage sweep at room temperature up to 275°C, and thermal aging at 150°C for up to more than 700 hours. High temperature encapsulants capable of producing leakage currents less than 1μA, are deemed acceptable at the given applied blocking voltage and thermal aging soak temperature. To fully characterize the high temperature encapsulants, silicone gel A, B, and C, an entire high temperature module is used as a common test vehicle. The power module test vehicle includes: 12mil/40mil/12mil Direct Bonded Copper (DBC) substrates, gel under test (GUT), power and Kelvin connected measurement terminals, thermistor thermal sensor to sense real-time temperature, and 12mil Al bonding wires to manage localized high E-Fields around wires. It was ultimately observed that silicone gels B and C were capable of maintaining low leakage current capabilities under 12kV and 275°C conditions, and thus present themselves as strong candidates for high-temperature WBG device power modules and packaging.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Morgan, Adam and Zhao, Xin and Rouse, Jason and Hopkins, Douglas}, year={2017}, month={Oct}, pages={000312–000317} } @article{zhao_jagannadham_reainthippayasakul_lanagan_hopkins_2017, title={Characterization of Ultra-Thin Epoxy-Resin Based Dielectric Substrate for Flexible Power Electronics Applications}, volume={2017}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2017-tp55_094}, DOI={10.4071/isom-2017-tp55_094}, abstractNote={Abstract Available substrate materials for power module applications has been investigated for a long time. Though Direct Bonded Copper (DBC) substrates, nowadays, have been widely applied in power electronics applications, especially power modules, due to its superior performance in mechanical ruggedness, thermal conductivity, and isolation capability. Its cost and complicated requirements during fabrication processes are always concerns in industries. At the same time, flexible electronics has become a rapidly expanding area with commercial applications including displays, medical, automotive, sensors arrays, wearable electronics, etc. This paper will initiate an investigation on a dielectric material that has potential in high power wearable electronics applications. A recently developed ultra-thin Epoxy-Resin Based Dielectric (ERBD) substrate material which is suitable for power electronic applications, is introduced. The ERBD can be fabricated with thickness as low as 80μm, with more than 5kV DC isolation capability. Its thermal conductivity is 8W/mK, higher than similar product currently available in the market. ERBD is also able to be bonded with Cu plates on both sides. In this paper, the properties of ERBD are investigated. Scanning Electron Microscope (SEM) is applied to analyze the microstructure of ERBD, and its bonding interface with Cu plates. 3-omega and Transient Thermal Reflectance methods are employed to precisely measure the thermal conductivity. Dielectric constant and loss are measured at different frequency. Simulations are applied to correct the error from the fringing effect during the measurement. The leakage current of ERBD is also measured under different voltage and temperature with DC and AC condition. Reliability tests are conducted to examine the electrical isolation and shearing strength of ERBD. The suitability of ERBD for potential flexible power electronics application is discussed based on the results from investigation of properties of the dielectric.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Zhao, Xin and Jagannadham, K. and Reainthippayasakul, Wuttichai and Lanagan, Michael T. and Hopkins, Douglas C.}, year={2017}, month={Oct}, pages={000151–000156} } @inproceedings{zhao_gao_jiang_zhang_wang_xu_nishiguchi_fukawa_hopkins_2017, title={Flexible epoxy resin substrate based 1.2 kV SiC half bridge module with ultra-low parasitics and high functionality}, DOI={10.1109/ecce.2017.8096700}, note={\urlhttps://ieeexplore.ieee.org/document/8096700/}, booktitle={2017 ieee energy conversion congress and exposition (ecce)}, author={Zhao, X. and Gao, B. and Jiang, Y. F. and Zhang, L. Q. and Wang, S. Z. and Xu, Y. and Nishiguchi, K. and Fukawa, Y. and Hopkins, Douglas C}, year={2017}, pages={4011–4018} } @misc{hopkins_2017, title={Grid Modernization – FREEDM Systems Center}, author={Hopkins, Douglas C.}, year={2017} } @inproceedings{hopkins_2017, title={Heterogeneous Integration Integrated Power Devices Roadmap}, author={Hopkins, Douglas C.}, year={2017} } @article{ke_jiang_morgan_hopkins_2017, title={Investigation of Package Effects on the Edge Termination E-Field for HV WBG Power Semiconductors}, volume={2017}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2017-wa32_092}, DOI={10.4071/isom-2017-wa32_092}, abstractNote={Abstract The edge termination of a power semiconductor is defined as the spatial junction terminations around the edges of the power devices. Guard rings are used to contour the internal depletion regions and E-fields as they terminate at the edge termination, i.e. the intersection of the depletion regions and the wafer saw line where the crystal damage is located. Since there is no specific package for WBG power devices, wire bonds are still widely used to interconnect to the topside metal pads of the power devices. From previous research it is shown that wire bonding will not affect the E-field around the guard rings on a WBG device. However, planar power package, such as double-sided and power flip-chip device packaging could be a problem where the close distance between the topside of the power device and conducting plane may negatively affect the E-field distribution of the guard rings, which in turn lowers the reverse blocking capability of the WBG power device and increases leakage current creating greater on-state power loss, or even early break down. Few works have shown the Electric field distribution in embedded power modules. Therefore, a more detailed investigation and possible solution is needed for the proliferation of double-sided power packages. To investigate this packaging problem simulations were performed in Sentaurus TCAD and COMSOL based on the device physics and package geometries. Guard ring structures in 1.2kV and 10kV SiC Schottky Barrier Diode (SBD) were built and simulated in various double-sided package geometries, together with the thermal and mechanical evaluation of the package, to observe the influence on the E-field distribution in and out the WBG device. Different double-sided package structures were evaluated and a guideline (spacing/pad size/etc.) summarized for double-sided design. Moreover, a new bevel edge termination method was evaluated for double-sided WBG power semiconductor devices. Experimental reverse blocking test results will be reported in various temperature (from 25°C to 175°C) to verify the function of the package. The tests are on 1200V/50A SiC SBD (Schottky Barrier Diode) from Global Power Technology, which has double-sided Ag on both sides.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Ke, Haotao and Jiang, Yifan and Morgan, Adam J. and Hopkins, Douglas C.}, year={2017}, month={Oct}, pages={000224–000230} } @article{zhao_jagannadham_hopkins_2017, title={Multiphysics Performance Evaluation of Flexible Substrate Based 1.2kV SiC Half Bridge Intelligent Power Module with Stacked Dies}, volume={2017}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2017-wp22_095}, DOI={10.4071/isom-2017-wp22_095}, abstractNote={Abstract Wide Bandgap (WBG) power devices have become the most promising solution for power conversion systems, with the best trade-off between theoretical characteristics, real commercial availability and maturity of fabrications. Advanced packaging technology is being heavily developed to take full advantages of WBG devices, in terms of materials, mechanical design, fabrication and electrical performance optimizations. In this paper, a flexible substrate based 1.2kV SiC Half Bridge Intelligent Power Module with stacked dies is introduced. The module design is based on the concept “Power Supply in Package (PSiP)”, high functionality is integrated in the module. Together with power stages, gate driver circuits, Low Dropout Regulators (LDO), digital isolators, and bootstrap circuits are integrated in the module. An ultra-thin flexible epoxy-resin based dielectric is applied in the module as substrates, its thickness can be as low as 80μm, with 8W/mK thermal conductivity. The SiC switches are double-side solderable, with copper as topside metallization on pads. No bonding wires are applied in the SiC PSiP module. The highside and lowside SiC switches on the phase leg is stacked vertically for interconnections with low parasitic and high denstiy. This work mainly addresses performance evaluation of the PSiP SiC half bridge module by multiphysics simulations. Q3D is employed to evaluate the parasitic inductance and resistance in the module, showing that parasitic inductance is lower than 1.5nH in the design. The extracted parasitics is imported in spice circuit model, simulation results show limited ringing during switching transients. Thermal simulations are employed to compare junction temperature of power modules with DBC subtrates and flexible substrates, then to evaluate the thermal performance of the designed PSiP SiC model with stacked dies. It shows that junction temperature of designed IPM is higher than regular module at same condition. The paper also provides guideline for optimized heat sink design to lower junction temperature of the SiC IPM. Mechanical simulations are employed to evaluate the pre-stress induced in modules with DBC substrate and flexible dielectric substrate, and proves that mechanical stress induced by reflowing process can be reduced significantly by using ultra-thin flexible dielectric as substrate.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Zhao, Xin and Jagannadham, K. and Hopkins, Douglas C.}, year={2017}, month={Oct}, pages={000353–000359} } @inproceedings{zhao_jiang_gao_nishiguchi_fukawa_hopkins_2017, title={Novel polymer substrate-based 1.2 kV/40 a double-sided intelligent power module}, DOI={10.1109/ectc.2017.285}, note={\urlhttp://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=7999873 ; \urlhttp://xplorestaging.ieee.org/ielx7/7998598/7999654/07999873.pdf?arnumber=7999873}, booktitle={2017 ieee 67th electronic components and technology conference (ectc 2017)}, author={Zhao, X. and Jiang, Y. F. and Gao, B. and Nishiguchi, K. and Fukawa, Y. and Hopkins, Douglas C}, year={2017}, pages={1461–1467} } @inproceedings{morgan_choobineh_fresne_hopkins_2017, title={Numerical and experimental determination of temperature distribution in 3D stacked power devices}, DOI={10.1115/ipack2017-74222}, note={\urlhttps://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2660938 ; \urlhttp://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2660938 ; \urlhttps://asmedigitalcollection.asme.org/InterPACK/proceedings/InterPACK2017/58097/V001T01A002/266226}, booktitle={Exhibition on packaging and integration of electronic and photonic}, author={Morgan, A. and Choobineh, L. and Fresne, D. and Hopkins, Douglas C}, year={2017} } @inproceedings{hopkins_ke_2017, title={True 3D Power Packaging - Higher Densities Through Orthogonality}, author={Hopkins, Douglas C. and Ke, Haotao}, year={2017} } @article{zhao_ke_jiang_morgan_xu_hopkins_2016, title={A High Performance Power Module with >10kV capability to Characterize and Test In Situ SiC Devices at >200°C Ambient}, volume={2016}, ISSN={2380-4491}, url={http://dx.doi.org/10.4071/2016-hitec-149}, DOI={10.4071/2016-hitec-149}, abstractNote={Abstract This paper presents design, fabrication and characterization details of a 10kV power module package for >200°C ambient temperature applications. Electrical simulations were performed to confirm the module design, and that the electric field distribution throughout the module did not exceed dielectric capabilities of components and materials. A suitable copper etching process was demonstrated for DBC layout, and a high melting point Sn/Pb/Ag solder reflow process was developed for device and component attachment. To monitor the operational temperature of the module, a thermistor was integrated onto the substrate. A new silicone gel, having a working temperature up to 210°C, was evaluated and selected for encapsulation and, of great importance, for passivation of high voltage (10kV) SiC dies. An additive manufacturing ‘Design Process’ was developed and applied to printing the housings, molds, and test fixtures. Also, cleaning processes were evaluated for every step in the fabrication process. To verify performance of the modules, mechanical dies were mounted on the substrates, and a high temperature testing setup built to characterize the modules at high temperature. Measurements indicated that the module can operate up to 12kV within 25°C to 225°C, with less than 0.1 μA leakage current. The packaging was used for full-power characterization of developmental 10kV SiC diodes, and proved that the power module packaging satisfied all requirements for high voltage and high temperature applications. This work successfully validated the processes for creating high voltage (>10 kV) and high temperature (>200°C) power modules.}, number={HiTEC}, journal={Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT)}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Zhao, Xin and Ke, Haotao and Jiang, Yifan and Morgan, Adam and Xu, Yang and Hopkins, Douglas C.}, year={2016}, month={Jan}, pages={000149–000158} } @inproceedings{hopkins_xu_ke_morgan_2016, title={A New Power Module Design Resource – Laboratory for Packaging Research in Electronic Energy Systems (PREES)}, author={Hopkins, Douglas C. and Xu, Yang and Ke, Haotao and Morgan, Adam}, year={2016} } @inproceedings{gao_hopkins_2016, title={A folded GaN VRM with high electrical and thermal performance}, ISBN={9781509029402}, url={http://dx.doi.org/10.1109/3dpeim.2016.7570564}, DOI={10.1109/3dpeim.2016.7570564}, booktitle={2016 International Symposium on 3D Power Electronics Integration and Manufacturing (3D-PEIM)}, publisher={IEEE}, author={Gao, Bo and Hopkins, D. C.}, year={2016}, month={Jun} } @misc{hopkins_2016, title={Additive Manufacturing – 3D Printing of Electronic Energy Systems and Beyond}, author={Hopkins, D.C.}, year={2016} } @inproceedings{zhao_xu_hopkins_2016, title={Advanced multi-physics simulation for high performance power electronic packaging design}, ISBN={9781509029402}, url={http://dx.doi.org/10.1109/3dpeim.2016.8048203}, DOI={10.1109/3dpeim.2016.8048203}, booktitle={2016 International Symposium on 3D Power Electronics Integration and Manufacturing (3D-PEIM)}, publisher={IEEE}, author={Zhao, Xin and Xu, Yang and Hopkins, Douglas C.}, year={2016}, month={Jun} } @inproceedings{xu_hopkins_2016, title={Application of 3D Printing for Rapid Prototyping of Advanced Power Electronic Modules}, author={Xu, Yang and Hopkins, Douglas C.}, year={2016} } @inproceedings{zhao_gao_hopkins_2016, title={Characterization of Ultra-Thin Flexible Ceramics for High-Density, 3D-Stackable Substrates for Wearable Power Electronics}, author={Zhao, Xin and Gao, Bo and Hopkins, Douglas C.}, year={2016} } @inproceedings{morgan_xu_hopkins_husain_yu_2016, title={Decomposition and electro-physical model creation of the CREE 1200V, 50A 3-Ph SiC module}, DOI={10.1109/apec.2016.7468163}, note={\urlhttps://ieeexplore.ieee.org/document/7468163 ; \urlhttps://works.bepress.com/kang-peng/10/download/ ; \urlhttps://works.bepress.com/kang-peng/10/}, booktitle={Apec 2016 31st annual ieee applied power electronics conference and exposition}, author={Morgan, A. J. and Xu, Y. and Hopkins, Douglas C and Husain, I. and Yu, W. S.}, year={2016}, pages={2141–2146} } @inproceedings{rahman_morgans_xu_gao_yu_hopkins_husain_2016, title={Design methodology for a planarized high power density EV/HEV traction drive using SiC power modules}, DOI={10.1109/ecce.2016.7855018}, note={\urlhttps://ieeexplore.ieee.org/document/7855018/}, booktitle={2016 ieee energy conversion congress and exposition (ecce)}, author={Rahman, D. and Morgans, A. J. and Xu, Y. and Gao, R. and Yu, W. S. and Hopkins, Douglas C and Husain, I.}, year={2016} } @inproceedings{de_morgan_iyer_ke_zhao_vechalapu_bhattacharya_hopkins_2016, title={Design, package, and hardware verification of a high voltage current switch}, DOI={10.1109/apec.2016.7467887}, note={\urlhttps://ieeexplore.ieee.org/document/7467887/}, booktitle={Apec 2016 31st annual ieee applied power electronics conference and exposition}, author={De, A. and Morgan, A. and Iyer, V. M. and Ke, H. and Zhao, X. and Vechalapu, K. and Bhattacharya, Subhashish and Hopkins, Douglas C}, year={2016}, pages={295–302} } @inproceedings{xu_husain_west_yu_hopkins_2016, title={Development of an ultra-high density power chip on bus (PCoB) module}, DOI={10.1109/ecce.2016.7855040}, note={\urlhttp://ieeexplore.ieee.org/document/7855040/}, booktitle={2016 ieee energy conversion congress and exposition (ecce)}, author={Xu, Y. and Husain, I. and West, H. and Yu, W. S. and Hopkins, Douglas C}, year={2016} } @inproceedings{xu_hopkins_2016, title={FEA-based thermal-mechanical optimization for DBC based power modules}, booktitle={2016 International Symposium on 3d Power Electronics Integration and Manufacturing (3d-PEIM)}, author={Xu, Y. and Hopkins, D.}, year={2016} } @misc{hopkins_2016, title={Misconception of Thermal Spreading Angle and Misapplication to PCB & Power Modules}, author={Hopkins, Douglas C.}, year={2016} } @article{zhao_jagannadham_reainthippayasakul_lanagan_hopkins_2016, title={Thermal and Electrical Characterizations of Ultra-Thin Flexible 3YSZ Ceramic for Electronic Packaging Applications}, volume={2016}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2016-tha13}, DOI={10.4071/isom-2016-tha13}, abstractNote={Abstract This paper presents thermal and electrical characterizations of an ultra-thin flexible 3YSZ (3 mol% Yttria Stabilized Zirconia) ceramic substrate to explore its potential for electronic packaging applications. The thicknesses of the ultra-thin 3YSZ substrates were 20 μm and 40 μm. The flexible thin ceramic substrate can provide not only better modulus for higher robustness in manufacturing, especially in Z-axis direction of modules, but also low thermal resistance for high density 2D (two dimensional) / 3D (three dimensional) power module packaging applications. To better understand the thermal and electrical properties of the ultra-thin flexible ceramic, different measurements were employed. Thermal conductivity was measured at different temperatures by 3-omega method, the results were verified by thermo-reflectance measurement at room temperature. Relative permittivity was measured from 100 Hz to 10 MHz, with dielectric losses determined by dielectric spectroscopy. The dielectric breakdown of the ultra-thin flexible 3YSZ was measured, from room temperature to 150 °C. Weibull analysis was performed on 20 measurements for each temperature. The test results showed that the thermal conductivity of 3YSZ decreased from 3.3 W/mK at 235 K to 2.2 W/Mk at 600 K. The relative permittivity decreased from 30.9 to 27.3 for higher frequencies for both substrates with different thickness. The temperature-dependence of relative permittivity and dielectric loss was studied. The results showed that these two parameters increased slowly from −65 °C to 150 °C, but more repidly from 175 °C to 250 °C. The dielectric breakdown decreased at higher temperature, from 5.76 kV to 2.64 kV for thickness of 20 μm, 7.84 kV to 3.36 kV for thickness of 40 μm. SEM (Scanning Electron Microscopy), EDS (Energy-dispersive X-ray Spectroscopy) and XRD (X-ray Powder Diffraction) analysis was performed to compare the microstructure of 3YSZ ultra-thin substrate and that of AlN (Aluminum Nitride) substrate. The microstructure of 3YSZ consisted of smaller round particles and that of AlN contained larger columnar particles. FEA (Finite Element Analysis) simulations were also applied to demonstrate the thermal properties of 3YSZ in simplified model of power modules. Though the measurement results showed that it did not meet expectations for high temperature power modules, the present work showed potential applications of the ultra-thin 3YSZ substrates in low voltage power modules, LED modules.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Zhao, Xin and Jagannadham, K. and Reainthippayasakul, Wuttichai and Lanagan, Michael. T. and Hopkins, Douglas C.}, year={2016}, month={Oct}, pages={000391–000396} } @inproceedings{zhao_ke_jiang_morgan_xu_hopkins_2016, title={Ultra Low Leakage Module for 12kV-225 ̊C SiC Semiconductor Testing}, author={Zhao, Xin and Ke, Haotao and Jiang, Yifan and Morgan, Adam and Xu, Yang and Hopkins, Douglas C.}, year={2016}, month={Oct} } @inproceedings{hopkins_2015, title={3D Power Electronics Packaging and Additive Manufacturing}, author={Hopkins, D.C.}, year={2015}, month={Nov} } @article{morgan_de_ke_zhao_vechalapu_hopkins_bhattacharya_2015, title={A Robust, Composite Packaging Approach for a High Voltage 6.5kV IGBT and Series Diode}, volume={2015}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2015-wp17}, DOI={10.4071/isom-2015-wp17}, abstractNote={The main motivation of this work is to design, fabricate, test, and compare an alternative, robust packaging approach for a power semiconductor current switch. Packaging a high voltage power semiconductor current switch into a single power module, compared to using separate power modules, offers cost, performance, and reliability advantages. With the advent of Wide-Bandgap (WBG) semiconductors, such as Silicon-Carbide, singular power electronic devices, where a device is denoted as a single transistor or rectifier unit on a chip, can now operate beyond 10kV–15kV levels and switch at frequencies within the kHz range. The improved voltage blocking capability reduces the number of series connected devices within the circuit, but challenges power module designers to create packages capable of managing the electrical, mechanical, and thermal stresses produced during operation. The non-sinusoidal nature of this stress punctuated with extremely fast changes in voltage and current, with respect to time, leads to non-ideal electrical and thermal performance. An optimized power semiconductor series current switch is fabricated using an IGBT (6500V/25A die) and SiC JBS Diode (6000V/10A), packaged into a 3D printed housing, to create a composite series current switch package (CSCSP). The final chosen device configuration was simulated and verified in an ANSYS software package. Also, the thermal behavior of such a composite package was simulated and verified using COMSOL. The simulated results were then compared with empirically obtained data, in order to ensure that the thermal ratings of the power devices were not exceeded; directly affecting the maximum attainable frequency of operation for the CSCSP. Both power semiconductor series current switch designs are tested and characterized under hard switching conditions. Special attention is given to ensure the voltage stress across the devices is significantly reduced.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Morgan, Adam and De, Ankan and Ke, Haotao and Zhao, Xin and Vechalapu, Kasunaidu and Hopkins, Douglas C. and Bhattacharya, Subhashish}, year={2015}, month={Oct}, pages={000359–000364} } @inproceedings{hopkins_2015, title={Additive Manufacturing (a.k.a. 3D Printing) for Designing Power Electronic Systems}, author={Hopkins, D.C.}, year={2015}, month={Oct} } @inproceedings{hopkins_ke_2015, title={Additive Manufacturing In Power Electronics Packaging}, author={Hopkins, D.C. and Ke, H.}, year={2015} } @inproceedings{de_morgan_bhattacharya_hopkins_2015, title={Design considerations of packaging a high voltage current switch}, booktitle={International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems, 2015, vol 3}, author={De, A. and Morgan, A. and Bhattacharya, S. and Hopkins, D. C.}, year={2015} } @inproceedings{morgan_hopkins_mckeown_2015, title={Physical Rf Circuit Techniques And The Implications On Future Power Module Design}, author={Morgan, A.J. and Hopkins, D.C. and McKeown, M.}, year={2015}, month={May} } @inproceedings{lawrence_hopkins_2015, title={The Evolution and Future Development of Power Electronics as an Essential Element of Power Generation/Delivery, Energy Efficiency, and Industrial Automation}, author={Lawrence, R. and Hopkins, D.C.}, year={2015}, month={Dec} } @inproceedings{sung_huang_baliga_ji_ke_hopkins_2015, title={The first demonstration of symmetric blocking SiC gate turn-off (GTO) thyristor}, ISBN={9781479962594 9781479962617}, url={http://dx.doi.org/10.1109/ISPSD.2015.7123438}, DOI={10.1109/ispsd.2015.7123438}, note={\urlhttps://ieeexplore.ieee.org/document/7123438/}, booktitle={2015 IEEE 27th International Symposium on Power Semiconductor Devices & IC's (ISPSD)}, publisher={IEEE}, author={Sung, Woongje and Huang, Alex Q. and Baliga, B. J. and Ji, Inhwan and Ke, Haotao and Hopkins, Douglas C.}, year={2015}, month={May}, pages={257–260} } @misc{ke_morgan_aman_hopkins_2014, title={3D Printing in the Micro- & Power-Electronics Packaging World}, author={Ke, H. and Morgan, A. and Aman, R. and Hopkins, D.C.}, year={2014} } @article{ke_morgan_aman_hopkins_2014, title={Investigation of Rapid-Prototyping Methods for 3D Printed Power Electronic Module Development}, volume={2014}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-thp52}, DOI={10.4071/isom-thp52}, abstractNote={The recent research in wide-bandgap (WBG) power electronic semiconductors has produced a wide variety of device and combinational topologies, such as HFETS, MOSHFETS, and the Cascode Pair. Each variation needs to be tested with certain package criteria (e.g. high voltage SiC devices up to 15kV, high current GaN devices up to 300A, or unprecedented high frequencies). Having a common package is costly and cannot provide an investigation of optimized performance. Hence, use of a rapid prototyping method to print power electronic packages and modules is needed. Also, the continual move to higher frequencies will require greater integration of packaging into the end application, as is presently done with point-of-load converters. The future modules will take on more functional integration, including more mechanical features, which further supports use of printed fabrication technologies. It is not reasonable to assume that a complete module can be directly printed, though most would be; some assembly is required. This paper discusses partitioning of a module process, and identifying key elements that can be combined for optimum power package production. To select the best process, or combination, for rapid-prototype printing of power modules current, Additive Manufacturing (AM) methods are evaluated, such as Stereolithography (SLA), Selective Laser sintering (SLS), and Fused Deposition Manufacturing (FDM). Several modules were fabricated to demonstrate mechanical resolutions in the packaging. A thermoplastic printer, specifically the MakerBot, which is a high end consumer 3D printer, produces packages with 100 micron resolution. The Acrylonitrile butadiene styrene (ABS) build object can have surface texture enhancement with post chemical treatment, such as an acetone vapor bath. Today, this is finding a home and proving useful in low volume rapid prototyping in small electronics companies. The ABS plastics are typically rated for <105°C applications. Another printed module to be reported uses a high-end commercial machine with <20 microns in resolution (Stratasys Objet) using standard UV curable polymers. This provides a slightly higher temperature range with greater mechanical integrity. Materials for >250°C that use both UV and thermal sintering are available, but not evaluated in this paper. Functional integration can include electrical, mechanical, and thermal appendages and sub-systems. Electrical sub-systems, such as gate drivers and sensors, can impact process partitioning, by requiring “low power” circuit fabrication processes integrated with those for high power. This paper demonstrates a printed polymer substrate process for functional integration of a signal-circuit. Since nearly all AM processes were developed initially for mechanical systems, many processed materials have not been electrically characterized, though the basic material compositions may have suitable electrical characteristics. This paper categorizes several materials for their potential suitability for power packaging. The evaluation is based on the electrical, mechanical, and thermal parameters, along with precision, surface texture (affecting electric field contours) and process times. Cost and performance will be of main concern.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Ke, Haotao and Morgan, Adam and Aman, Ronald and Hopkins, Douglas C}, year={2014}, month={Oct}, pages={000887–000892} } @inproceedings{xu_hopkins_2014, title={Misconception of thermal spreading angle and misapplication to IGBT power modules}, DOI={10.1109/apec.2014.6803362}, note={\urlhttps://ieeexplore.ieee.org/document/6803362}, booktitle={2014 twenty-ninth annual ieee applied power electronics conference and exposition (apec)}, author={Xu, Y. and Hopkins, Douglas C}, year={2014}, pages={545–551} } @inproceedings{hopkins_xu_ke_2014, title={Printed Interfacial Interconnects in High Power Module}, author={Hopkins, D.C. and Xu, Y. and Ke, H.}, year={2014} } @book{xu_hopkins_2014, title={Thermal-mechanical design and optimization for DBC based power modules}, author={Xu, Yang and Hopkins, D.C.}, year={2014} } @article{ke_xu_hopkins_2013, title={Conceptual Development Using 3D Printing Technologies for 8kV SiC Power Module Package}, volume={2013}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2013-wp62}, DOI={10.4071/isom-2013-wp62}, abstractNote={Post-silicon power devices, SiC or GaN for example, have many advantages over traditional silicon devices, particularly for smaller size and higher thermal densities. Although these devices are in the early stage of development, many applications have been identified, such as hybrid vehicles and the smart grid. For power packaging, there is now a greater challenge of much higher voltage, faster switching speed and much smaller package size (higher density). All of these issues call for newer approaches in power packaging. The microelectronics area has been developing stacked 3D technology along with printed 3D circuit technologies. Of been interested are the 3D printing technologies that can implement complicated structures, such as multilevel interconnects and selective dielectric field enhancements, besides introducing rapid prototyping in the early power stage design cycle. The 3D printing technology, introduced in the late 1980's, is now becoming prevalent. Commercial printers can create high-resolution structures in ceramic, metals (e.g. titanium, copper and aluminum) and polymers. The conceptual design proposed in this paper will incorporate a hybrid approach of traditional structures over-printed with polymers, or more advanced structures over-printed with metal and ceramic. The design focuses on packaging 1 cm × 1 cm SiC Schottky diode, which has a blocking capability of 8kV with a final target at 15kV. Early use of the package, in keeping with rapid prototyping, is to provide a test vehicle for the device, and prove the application of 3D printed material to high voltage power modules. This paper will present the necessity for packaging new SiC devices, review device characteristics, introduce the use of extruded 3D printing materials for a hybrid structure, and use of jetted/extruded layer-by-layer buildup for total, direct structure creation. Characterization of some available dielectric and metal printable materials, and a test methodology for electrical, thermal and mechanical performance will be discussed. An early-stage example will be shown and extrapolated to higher-level conceptual designs.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Ke, Haotao and Xu, Yang and Hopkins, Douglas C}, year={2013}, month={Jan}, pages={000758–000763} } @inproceedings{bhat_oh_hopkins_2013, title={Feasibility of a MEMS sensor for gas detection in HV oil-insulated transformer}, volume={49}, DOI={10.1109/tia.2012.2229681}, note={\urlhttps://ieeexplore.ieee.org/document/6361292/ ; \urlhttps://www.researchgate.net/profile/DC_Hopkins/publication/260706240_Feasibility_of_a_MEMS_Sensor_for_Gas_Detection_in_HV_Oil-Insulated_Transformer/links/54170b2f0cf2218008bec49d.pdf}, number={1}, booktitle={IEEE Transactions on Industry Applications}, author={Bhat, K. P. and Oh, K. W. and Hopkins, Douglas C}, year={2013}, pages={316–321} } @inproceedings{hopkins_2013, title={Understanding Impact of New Additive Manufacturing Techniques on Power Electronics Design}, author={Hopkins, D.C.}, year={2013}, month={Mar} } @article{ke_hopkins_2012, title={Development of Printed Power Packaging for a High Voltage SiC Module}, volume={2012}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2012-wp55}, DOI={10.4071/isom-2012-wp55}, abstractNote={Due to rapidly developing post silicon power devices, in particular SiC and GaN, three primary parameters in power packaging: temperature, voltage and current, are much more difficult to manage. The SiC devices are being developed for high voltage (>15kV). The GaN devices will have extremely low internal resistance, operate at extreme current densities (≫10A/mm2), and can account for <50% of the resistance in a power module. Both devices can operate at high temperatures (>300°C) and >10-times frequency compared to Si. The traditional power electronics packaging approaches need augmentation or replacement. Most technologies used in packaging of power electronic systems, or more generally Electronic Energy Systems, are ported from microelectronics. The recent development of printable 3D circuit techniques, e.g. jetting and dispensing, provide additional major approaches applicable to power packaging. Some printing techniques are already applied to solar cells and batteries. This paper explores the printable electronics technologies for application to power.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Ke, Haotao and Hopkins, Douglas C}, year={2012}, month={Jan}, pages={000955–000960} } @article{hopkins_baltis_pitaress_hazelmyer_2012, title={Extreme Thermal Transient Stress Analysis with Pre-Stress in a Metal Matrix Composite Power Package}, volume={2012}, ISSN={2380-4491}, url={http://dx.doi.org/10.4071/hitec-2012-tha25}, DOI={10.4071/hitec-2012-tha25}, abstractNote={This paper culminates several years of development of a SiC MOSFET-based solid-state circuit breaker power module designed and fabricated for aluminum-based composite metal-ceramic packaging. The aluminum composite structure was used for high temperature thermal management >350°C and high reliability. Testing of the final module surpassed 750 total cycles. The module was optimized for four dies, 4.1mm × 4.1 mm each for SiC or GaN. The electrically loading per die was 48 A for 5 ms with a di/dt of 2.1 kA/us (23 ns opening time). An internal snubber increased the response to 390 ns. The die absorbed ∼4.6 J causing a transient junction temperature increase of ∼245 °C. Two ambient temperatures were used in testing and set at 25 °C and 105 °C. The maximum junction temperature was conservatively projected to reach 350 °C during the 5 ms pulse. Electrical, thermal and mechanical design and testing results are presented.}, number={HITEC}, journal={Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT)}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Hopkins, Douglas C. and Baltis, Theodore and Pitaress, James M and Hazelmyer, Donald R.}, year={2012}, month={Jan}, pages={000361–000372} } @inproceedings{basaran_li_hopkins_yao_2012, title={Mean time to failure of SnAgCuNi solder joints under DC}, ISBN={9781424495320 9781424495337 9781424495313}, url={http://dx.doi.org/10.1109/itherm.2012.6231474}, DOI={10.1109/itherm.2012.6231474}, booktitle={13th InterSociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems}, publisher={IEEE}, author={Basaran, Cemal and Li, Shidong and Hopkins, Douglas C. and Yao, Wei}, year={2012}, month={May} } @inproceedings{hopkins_2012, title={Point Source Thermal Management in Dense Power Modules and Systems}, author={Hopkins, D.C.}, year={2012} } @inproceedings{hopkins_2012, title={Printable Packaging for High Power, High Temperature Power Module}, author={Hopkins, D.C.}, year={2012} } @inproceedings{bhat_guo_xu_baltis_hazelmyer_hopkins_2012, title={Results for an Al/AlN composite 350°C SiC solid-state circuit breaker module}, ISBN={9781457712166 9781457712159 9781457712142}, url={http://dx.doi.org/10.1109/apec.2012.6166172}, DOI={10.1109/apec.2012.6166172}, booktitle={2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Bhat, Krishna P. and Guo, Yuan-Bo and Xu, Yang and Baltis, Theodore and Hazelmyer, Donald R. and Hopkins, Douglas C.}, year={2012}, month={Feb} } @article{baltis_hopkins_pitaressi_hazelmyer_2011, title={High Thermal-Transient Packaging for a SiC-Based Solid State Circuit Breaker}, volume={2011}, ISSN={2380-4505}, url={http://dx.doi.org/10.4071/isom-2011-wa5-paper2}, DOI={10.4071/isom-2011-wa5-paper2}, abstractNote={Solid-State Circuit Breakers (SSCBs), or Contactors, are critical components in next generation electric aircraft, and must be small in size, fast in response, and have high reliability. Silicon Carbide (SiC) semiconductor switches provide a series of improvements over traditional silicon-based breakers in both electrical and thermal performances. The reported SSCB uses SiC MOSFETs mounted on cast-aluminum traces, cast onto an aluminum nitride (AlN) ceramic co-captured in an aluminum composite baseplate. The system is similar to an AlSiC and Direct-Bonded-Aluminum (DBA) approach. This presentation details the transient thermal characterizations of an SSCB having the highest density in development. Previous work focused on a 30A SSCB that was constructed and tested to show a 300A, 500ns circuit breaking capability. The high density comes from allowing the SiC junctions to pulse to ∼350°C (in 5ms) from a 105°C ambient baseplate. The 30A/300A module was reported in IMAPS HiTEC’10 “Development of a SiC SSPC Module with Advanced High Temperature Packaging,” This paper builds on that paper adding the mechanical results and all new data on the larger, high energy density module with larger die. The objective of the presentation is to introduce (or update) the use of cast composite metal-ceramic structures for high thermal transient applications and document the mechanical stress/strain performance through simulations. The module is in development for military applications and has not been field-tested. This is also developed for Smart-Grid applications in local distribution systems.}, number={1}, journal={International Symposium on Microelectronics}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Baltis, Theodore and Hopkins, Douglas C and Pitaressi, James M and Hazelmyer, Donald R}, year={2011}, month={Jan}, pages={000608–000618} } @inproceedings{guo_bhat_aravamudhan_hopkins_hazelmyer_2011, title={High current and thermal transient design of a SiC SSPC for aircraft application}, ISBN={9781424480845}, url={http://dx.doi.org/10.1109/apec.2011.5744759}, DOI={10.1109/apec.2011.5744759}, booktitle={2011 Twenty-Sixth Annual IEEE Applied Power Electronics Conference and Exposition (APEC)}, publisher={IEEE}, author={Guo, Yuan-Bo and Bhat, Krishna P. and Aravamudhan, Arunkumar and Hopkins, Douglas C. and Hazelmyer, Donald R.}, year={2011}, month={Mar} } @inbook{hopkins_2011, place={Burlington, MA}, edition={3rd}, title={Packaging and Smart Power Systems}, ISBN={9780123820365}, url={http://dx.doi.org/10.1016/b978-0-12-382036-5.00044-6}, DOI={10.1016/b978-0-12-382036-5.00044-6}, booktitle={Power Electronics Handbook}, publisher={Butterworth-Heinemann/Elsevier}, author={Hopkins, Douglas C.}, editor={Rashid, Muhammad H.Editor}, year={2011}, pages={1275–1286} } @inproceedings{bhat_oh_hopkins_2010, title={A MEMS Sensor for Gas Detection in High Voltage Oil Filled Equipment}, ISBN={9781424463930}, url={http://dx.doi.org/10.1109/ias.2010.5615297}, DOI={10.1109/ias.2010.5615297}, booktitle={2010 IEEE Industry Applications Society Annual Meeting}, publisher={IEEE}, author={Bhat, Krishna Prasad and Oh, Kwang W. and Hopkins, Douglas C.}, year={2010}, month={Oct} } @inproceedings{bhat_hopkins_2010, title={Augmenting Bucholz Relay Using Embedded Mems Gas Sensor}, author={Bhat, K.P. and Hopkins, D.C.}, year={2010} } @inproceedings{hopkins_guo_aravamudhan_scofield_2010, title={Development and Testing of a 350 ̊C SiC MCPM with Cast Metal Matrix Composites}, author={Hopkins, D.C. and Guo, Y.B. and Aravamudhan, A. and Scofield, J.D.}, year={2010} } @article{hopkins_guo_dwyer_scofield_2010, title={Development of a SiC SSPC Module with Advanced High Temperature Packaging}, volume={2010}, ISSN={2380-4491}, url={http://dx.doi.org/10.4071/hitec-dhopkins-wp25}, DOI={10.4071/hitec-dhopkins-wp25}, abstractNote={Development of a multi-chip power module (MCPM) is reported that uses advanced metal-matrix composite aluminum packaging to manage high thermally induced stresses in devices that incur 350°C transients. The MCPM uses parallel SiC devices to control 120A DC nominal, 1200A fault in a 270V DC system. Electrical system modeling is presented to characterize electrical fault transients that induce electrical and thermal stresses in the semiconductors and packaging. The characterization of the advanced aluminum-based packaging system, which uses composites, such as AlSiC, and direct bonded aluminum (DBA), is discussed to manage the thermal stresses and transient heat flow.}, number={HITEC}, journal={Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT)}, publisher={IMAPS - International Microelectronics Assembly and Packaging Society}, author={Hopkins, Douglas C and Guo, Yuan-Bo and Dwyer, Herbert E and Scofield, James D.}, year={2010}, month={Jan}, pages={000310–000315} } @inproceedings{hopkins_2010, title={Solid-State Protection: Dual-use for Microgrids}, author={Hopkins, D.C.}, year={2010} } @inproceedings{wang_du_guo_hopkins_bhattacharya_huang_2009, title={A 6.5kV IGBT Development Module for Renewable Energy Systems}, author={Wang, G. and Du, Y. and Guo, Y. and Hopkins, D.C. and Bhattacharya, S. and Huang, A.}, year={2009} } @article{hosny_hopkins_gay_safiuddin_2009, title={A Dynamic Model for a Gas-Liquid Corona Discharge Using Neural Networks}, volume={24}, ISSN={0885-8977 1937-4208}, url={http://dx.doi.org/10.1109/tpwrd.2008.2005880}, DOI={10.1109/tpwrd.2008.2005880}, number={3}, journal={IEEE Transactions on Power Delivery}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Hosny, A.A. and Hopkins, D.C. and Gay, Z.B. and Safiuddin, M.}, year={2009}, month={Jul}, pages={1234–1239} } @inproceedings{hopkins_guo_jao_2009, title={Assessment of Critical Issues for High Temperature, High Voltage Power Modules}, author={Hopkins, D.C. and Guo, Y.B. and Jao, P.F.}, year={2009} } @inproceedings{basaran_li_hopkins_veychard_2009, title={Electromigration Time to Failure of SnAgCuNi Solder Joints}, author={Basaran, Cemal and Li, Shidong and Hopkins, Douglas C. and Veychard, Damien}, year={2009} } @article{basaran_li_hopkins_veychard_2009, title={Electromigration time to failure of SnAgCuNi solder joints}, volume={106}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.3159012}, DOI={10.1063/1.3159012}, number={1}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Basaran, Cemal and Li, Shidong and Hopkins, Douglas C. and Veychard, Damien}, year={2009}, month={Jul}, pages={013707} } @inproceedings{guo_jao_hopkins_2009, title={Investigation of High Electrical Gradients in High Voltage Power Modules}, author={Guo, Y.B. and Jao, P.F. and Hopkins, D.C.}, year={2009} } @inproceedings{guo_jao_wang_du_bhattacharya_hopkins_2009, title={Investigation of SiC Power Module Requirement for Smart Grid Applications}, author={Guo, Y. and Jao, P.F. and Wang, G. and Du, Y. and Bhattacharya, S. and Hopkins, D.C.}, year={2009} } @inproceedings{abdulhamid_hopkins_basaran_2008, title={Low Temperature Electromigration and Thermomigration in Lead-Free Solder Joints}, author={Abdulhamid, M. and Hopkins, D.C. and Basaran, C.}, year={2008} } @inproceedings{hopkins_kellerman_2008, title={Stress Management in a High Temperature Multilayered Composite Structure}, author={Hopkins, D.C. and Kellerman, D.W.}, year={2008} } @inproceedings{enser_hopkins_basaran_2007, title={A Review of Electromigration Under Time Varying Current Stressing}, author={Enser, Kevin E. and Hopkins, Douglas C. and Basaran, Cernal}, year={2007}, month={Apr} } @inproceedings{mckay_hopkins_basaran_abdulhamid_2007, title={Harsh Environment Thermal Management Using Aluminum-Based Packaging}, author={McKay, T. and Hopkins, D.C. and Basaran, C. and Abdulhamid, M.F.}, year={2007} } @inproceedings{abdulhamid_hopkins_basaran_2007, title={IMC Effects in Solder from High Thermal Gradients Management}, author={Abdulhamid, M.F. and Hopkins, D.C. and Basaran, C.}, year={2007} } @inbook{hopkins_2007, place={Burlington, MA}, edition={2nd}, title={Packaging and Smart Power Systems}, ISBN={9780120884797}, url={http://dx.doi.org/10.1016/b978-012088479-7/50060-2}, DOI={10.1016/b978-012088479-7/50060-2}, booktitle={Power Electronics Handbook}, publisher={Academic Press/Elsevier}, author={Hopkins, Douglas C.}, editor={Rashid, Muhammad H.Editor}, year={2007}, pages={1147–1158} } @inproceedings{enser_hopkins_basaran_2007, place={Washington, D.C.}, title={Solder Interconnect Electromigration Due to Time Varying Current Stressing}, volume={10}, booktitle={Proceedings of the 2007 International Symposium on Microelectronics : November 11-15, 2007, San Jose Convention Center, San Jose, California, USA}, publisher={IMAPS}, author={Enser, K.E. and Hopkins, D.C. and Basaran, C.}, year={2007} } @inproceedings{mckay_hopkins_basaran_2007, place={Washington, D.C.}, title={The effect of layer thickness variation on the thermo-mechanical properties of direct aluminum bonded substrates on AlSiC}, booktitle={Proceedings of the 2007 International Symposium on Microelectronics : November 11-15, 2007, San Jose Convention Center, san Jose, California, USA}, publisher={IMAPS}, author={McKay, T. and Hopkins, D.C. and Basaran, C.}, year={2007} } @inproceedings{hopkins_kellerman_basaran_gomez_2006, place={Washington, D.C.}, title={Aluminum-Based High-Temperature (>200°C) Packaging for SiC Power Converters}, booktitle={Proceedings 2006 International Symposium on Microelectronics : October 8-12, 2006 : San Diego Convention Center, San Diego, Calif.}, publisher={IMAPS}, author={Hopkins, D.C. and Kellerman, D.W. and Basaran, C. and Gomez, J.}, year={2006}, pages={734–741} } @article{ye_basaran_hopkins_2006, title={Experimental Damage Mechanics of Micro/Power Electronics Solder Joints under Electric Current Stresses}, volume={15}, ISSN={1056-7895 1530-7921}, url={http://dx.doi.org/10.1177/1056789506054311}, DOI={10.1177/1056789506054311}, abstractNote={ Experimental damage mechanics of flip chip solder joints under current stressing is studied using 20 test vehicle flip chip modules. Three different failure modes are observed. The dominant damage mechanism is caused by the combined effect of electromigration and thermomigration, where void nucleation and growth lead to the ultimate failure of the module. It is observed that thermomigration driving forces are stronger than electromigration; as a result thermomigration, not electromigration, determines the site of void nucleation. The void nucleation and growth modes and their preferred sites are also observed and discussed in detail. The interface between the Ni barrier layer and the solder joint is found to be the favorite site of void nucleation and growth. The effect of pre-existing voids on the failure process of a solder joint is also studied. It is observed that Black’s time to failure law for thin films is unreliable for solder joints. }, number={1}, journal={International Journal of Damage Mechanics}, publisher={SAGE Publications}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2006}, month={Jan}, pages={41–67} } @inproceedings{abdulhamid_basaran_hopkins_2006, title={Experimental Study of Thermomigration in Lead-Free Nanoelectronics Solder Joints}, ISBN={0791847691}, url={http://dx.doi.org/10.1115/imece2006-13119}, DOI={10.1115/imece2006-13119}, abstractNote={The study of thermomigration on Sn-Ag-Cu solder sphere subjected to a high thermal gradient of 1100°C/cm is presented. After 286 hours, the hot end showed a thin and flat intermetallic compound (IMC) while the cold side showed a scallop-like Cu6Sn5 IMC. Small voids can be seen within the Cu6Sn5 IMC after 712 hours on the cold side, while the IMC on the opposite side showed no observable changes.}, booktitle={Electronic and Photonic Packaging, Electrical Systems Design and Photonics, and Nanotechnology}, publisher={ASMEDC}, author={Abdulhamid, Mohd F. and Basaran, Cemal and Hopkins, Douglas C.}, year={2006}, month={Jan} } @inproceedings{hopkins_kellerman_wunderlich_basaran_gomez_2006, title={High-temperature, high-density packaging of a 60kW converter for >200/spl deg/C embedded operation}, ISBN={0780395476}, url={http://dx.doi.org/10.1109/apec.2006.1620641}, DOI={10.1109/apec.2006.1620641}, booktitle={Twenty-First Annual IEEE Applied Power Electronics Conference and Exposition, 2006. APEC '06.}, publisher={IEEE}, author={Hopkins, D.C. and Kellerman, D.W. and Wunderlich, R.A. and Basaran, C. and Gomez, J.}, year={2006}, month={Apr} } @article{basaran_ye_hopkins_frear_lin_2005, title={Flip chip solder joint failure modes}, volume={14}, number={10}, journal={Advanced Packaging}, author={Basaran, C. and Ye, H. and Hopkins, D.C. and Frear, D. and Lin, J.K.}, year={2005}, month={Oct}, pages={14–19} } @inproceedings{thondapu_hopkins_holguin_2005, title={Implementing Digital Power Control In Automotive Alternators}, author={Thondapu, C. and Hopkins, D.C. and Holguin, G.}, year={2005} } @inproceedings{ye_basaran_hopkins_lin_2005, title={Modeling deformation in microelectronics BGA solder joints under high current density. Part I. Simulation and testing}, ISBN={0780389069}, url={http://dx.doi.org/10.1109/ectc.2005.1441975}, DOI={10.1109/ectc.2005.1441975}, booktitle={Proceedings Electronic Components and Technology, 2005. ECTC '05.}, publisher={IEEE}, author={Ye, Hua and Basaran, C. and Hopkins, D.C. and Lin, Minghui}, year={2005}, month={Jul} } @inproceedings{ye_basaran_hopkins_frear_lin_2004, title={Damage mechanics of microelectronics solder joints under high current densities}, ISBN={0780383656}, url={http://dx.doi.org/10.1109/ectc.2004.1319460}, DOI={10.1109/ectc.2004.1319460}, booktitle={2004 Proceedings. 54th Electronic Components and Technology Conference (IEEE Cat. No.04CH37546)}, publisher={IEEE}, author={Ye, Hua and Basaran, C. and Hopkins, D.C. and Frear, D. and Lin, Jong-Kai}, year={2004}, month={Sep} } @inproceedings{basaran_ye_hopkins_2004, title={Deformation of Solder Joints Under Current Stressing: Experimental Measurement and Numerical Simulation}, author={Basaran, C. and Ye, H. and Hopkins, D.C.}, year={2004} } @article{ye_basaran_hopkins_2004, title={Deformation of solder joint under current stressing and numerical simulation––I}, volume={41}, ISSN={0020-7683}, url={http://dx.doi.org/10.1016/j.ijsolstr.2004.04.002}, DOI={10.1016/j.ijsolstr.2004.04.002}, number={18-19}, journal={International Journal of Solids and Structures}, publisher={Elsevier BV}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2004}, month={Sep}, pages={4939–4958} } @article{ye_basaran_hopkins_2004, title={Deformation of solder joint under current stressing and numerical simulation––II}, volume={41}, ISSN={0020-7683}, url={http://dx.doi.org/10.1016/j.ijsolstr.2004.04.003}, DOI={10.1016/j.ijsolstr.2004.04.003}, number={18-19}, journal={International Journal of Solids and Structures}, publisher={Elsevier BV}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C}, year={2004}, month={Sep}, pages={4959–4973} } @article{basaran_ye_hopkins_frear_lin_2004, title={Failure Modes of Flip Chip Solder Joints Under High Electric Current Density}, volume={127}, ISSN={1043-7398 1528-9044}, url={http://dx.doi.org/10.1115/1.1898338}, DOI={10.1115/1.1898338}, abstractNote={The failure modes of flip chip solder joints under high electrical current density are studied experimentally. Three different failure modes are reported. Only one of the failure modes is caused by the combined effect of electromigration and thermomigration, where void nucleation and growth contribute to the ultimate failure of the module. The Ni under bump metallization–solder joint interface is found to be the favorite site for void nucleation and growth. The effect of pre-existing voids on the failure mechanism of a solder joint is also investigated}, number={2}, journal={Journal of Electronic Packaging}, publisher={ASME International}, author={Basaran, C. and Ye, H. and Hopkins, D. C. and Frear, D. and Lin, J. K.}, year={2004}, month={Sep}, pages={157–163} } @article{ye_basaran_hopkins_2004, title={Mechanical Implications of High Current Densities in Flip-chip Solder Joints}, volume={13}, ISSN={1056-7895 1530-7921}, url={http://dx.doi.org/10.1177/1056789504044282}, DOI={10.1177/1056789504044282}, abstractNote={ We studied the electromigration damage to flip-chip solder joints of eutectic Sn/Pb under current stressing at room temperature with a current density of 1.3 × 104}, number={4}, journal={International Journal of Damage Mechanics}, publisher={SAGE Publications}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2004}, month={Oct}, pages={335–345} } @article{ye_basaran_hopkins_2004, title={Pb phase coarsening in eutectic Pb/Sn flip chip solder joints under electric current stressing}, volume={41}, ISSN={0020-7683}, url={http://dx.doi.org/10.1016/j.ijsolstr.2003.12.001}, DOI={10.1016/j.ijsolstr.2003.12.001}, number={9-10}, journal={International Journal of Solids and Structures}, publisher={Elsevier BV}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2004}, month={May}, pages={2743–2755} } @article{ye_basaran_hopkins_2003, title={Damage mechanics of microelectronics solder joints under high current densities}, volume={40}, ISSN={0020-7683}, url={http://dx.doi.org/10.1016/s0020-7683(03)00175-6}, DOI={10.1016/s0020-7683(03)00175-6}, number={15}, journal={International Journal of Solids and Structures}, publisher={Elsevier BV}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2003}, month={Jul}, pages={4021–4032} } @article{ye_basaran_hopkins_liu_cartright_2003, title={Flip Chip and BGA Solder Joint Reliability}, volume={12}, number={5}, journal={Advanced Packaging}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C. and Liu, Heng and Cartright, Alexander}, year={2003}, month={May}, pages={17–19} } @article{ye_hopkins_basaran_2003, title={Measurement of Electrical Current Density Effects in Solder Joints}, volume={30}, number={5}, journal={Advancing Microelectronics}, author={Ye, Hua and Hopkins, Douglas C. and Basaran, Cemal}, year={2003}, month={Sep} } @article{ye_hopkins_basaran_2003, title={Measurement of high electrical current density effects in solder joints}, volume={43}, ISSN={0026-2714}, url={http://dx.doi.org/10.1016/s0026-2714(03)00131-8}, DOI={10.1016/s0026-2714(03)00131-8}, number={12}, journal={Microelectronics Reliability}, publisher={Elsevier BV}, author={Ye, Hua and Hopkins, Douglas C. and Basaran, Cemal}, year={2003}, month={Dec}, pages={2021–2029} } @article{ye_basaran_hopkins_2003, title={Measuring Joint Reliability: Applying the Moire Interferometry Technique}, volume={12}, number={5}, journal={Advanced Microelectronics Magazine}, author={Ye, H. and Basaran, C. and Hopkins, D.C.}, year={2003}, month={May}, pages={17–20} } @article{ye_basaran_hopkins_2003, title={Mechanical degradation of microelectronics solder joints under current stressing}, volume={40}, ISSN={0020-7683}, url={http://dx.doi.org/10.1016/j.ijsolstr.2003.08.019}, DOI={10.1016/j.ijsolstr.2003.08.019}, number={26}, journal={International Journal of Solids and Structures}, publisher={Elsevier BV}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas C.}, year={2003}, month={Dec}, pages={7269–7284} } @article{ye_basaran_hopkins_2003, title={Numerical simulation of stress evolution during electromigration in IC interconnect lines}, volume={26}, ISSN={1521-3331}, url={http://dx.doi.org/10.1109/tcapt.2003.817877}, DOI={10.1109/tcapt.2003.817877}, number={3}, journal={IEEE Transactions on Components and Packaging Technologies}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Ye, Hua and Basaran, C. and Hopkins, D.C.}, year={2003}, month={Sep}, pages={673–681} } @inproceedings{hopkins_moronski_2003, title={Partitioning digitally programmable power-control for applications to ballasts}, ISBN={0780374045}, url={http://dx.doi.org/10.1109/apec.2002.989356}, DOI={10.1109/apec.2002.989356}, booktitle={APEC. Seventeenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.02CH37335)}, publisher={IEEE}, author={Hopkins, D.C. and Moronski, J.}, year={2003}, month={Jun} } @inproceedings{ye_basaran_hopkins_cartwright_2003, title={Reliability of solder joints under electrical stressing - strain evolution of solder joints}, ISBN={0780371526}, url={http://dx.doi.org/10.1109/itherm.2002.1012558}, DOI={10.1109/itherm.2002.1012558}, booktitle={ITherm 2002. Eighth Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (Cat. No.02CH37258)}, publisher={IEEE}, author={Ye, Hua and Basaran, C. and Hopkins, D. and Cartwright, A.}, year={2003}, month={Jun} } @article{ye_basaran_hopkins_2003, title={Thermomigration in Pb–Sn solder joints under joule heating during electric current stressing}, volume={82}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.1554775}, DOI={10.1063/1.1554775}, number={7}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas}, year={2003}, month={Feb}, pages={1045–1047} } @inproceedings{hopkins_mathuna_alderman_flannery_2002, title={A framework for developing power electronics packaging}, ISBN={0780343409}, url={http://dx.doi.org/10.1109/apec.1998.647663}, DOI={10.1109/apec.1998.647663}, booktitle={APEC '98 Thirteenth Annual Applied Power Electronics Conference and Exposition}, publisher={IEEE}, author={Hopkins, D.C. and Mathuna, S.C.O. and Alderman, A.N. and Flannery, J.}, year={2002}, month={Nov} } @inproceedings{craig_hopkins_driscoll_2002, title={A high speed pulser thyristor}, ISBN={0780343409}, url={http://dx.doi.org/10.1109/apec.1998.653980}, DOI={10.1109/apec.1998.653980}, booktitle={APEC '98 Thirteenth Annual Applied Power Electronics Conference and Exposition}, publisher={IEEE}, author={Craig, A.H. and Hopkins, D.C. and Driscoll, J.C.}, year={2002}, month={Nov} } @inproceedings{hopkins_bowers_2002, title={Characterization of advanced materials for high voltage/high temperature power electronics packaging}, ISBN={0780366182}, url={http://dx.doi.org/10.1109/apec.2001.912498}, DOI={10.1109/apec.2001.912498}, booktitle={APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181)}, publisher={IEEE}, author={Hopkins, D.C. and Bowers, J.S.}, year={2002}, month={Nov} } @inproceedings{ye_basaran_hopkins_2002, place={SPIE}, title={Experimental Study on Reliability of Solder Joints under Electrical Stressing -Nano-indentation, Atomic Flux Measurement}, volume={4828}, booktitle={SPIE proceedings series}, publisher={Bellingham, Washington}, author={Ye, H. and Basaran, C. and Hopkins, D.}, year={2002}, pages={231–236} } @inproceedings{ye_hopkins_basaran_2002, title={Measurement and Effects of High Electrical Current Stress in Solder Joints}, booktitle={Proceedings of the 35th International Symposium on Microelectronics}, author={Ye, H. and Hopkins, D.C. and Basaran, C.}, year={2002}, pages={427–432} } @inproceedings{ye_basaran_hopkins_2002, title={Mechanical Implications of High Current Densities in Flip Chip Solder Joints}, ISBN={0791836487}, url={http://dx.doi.org/10.1115/imece2002-33650}, DOI={10.1115/imece2002-33650}, abstractNote={The electromigration damage in flip chip solder joints of eutectic SnPb was studied under current stressing at room temperature with the current density about 1.3×104A/cm2. The diameter of the solder joints was about 140μm. The mass accumulation near anode side and void nucleation near cathode were observed during current stressing. The nano-indentation test was first time done on solder joints for electromigration test. Surface marker movement was used to measure the atomic flux driven by electromigration and to calculate the product of effective charge number and diffusivity, DxZ*, of the solder at room temperature. The effective charge number can be extracted with the solder diffusivity at room temperature known.}, booktitle={Electronic and Photonic Packaging, Electrical Systems Design and Photonics, and Nanotechnology}, publisher={ASMEDC}, author={Ye, Hua and Basaran, Cemal and Hopkins, Douglas}, year={2002}, month={Jan} } @inproceedings{jacobsen_hopkins_2002, title={Optimally selecting packaging technologies and circuit partitions based on cost and performance}, ISBN={0780358643}, url={http://dx.doi.org/10.1109/apec.2000.826079}, DOI={10.1109/apec.2000.826079}, booktitle={APEC 2000. Fifteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.00CH37058)}, publisher={IEEE}, author={Jacobsen, J.B. and Hopkins, D.C.}, year={2002}, month={Nov} } @inproceedings{bowers_hopkins_sarjeant_2002, title={Packaging issues for next generation high voltage, high temperature power electronic modules}, ISBN={0780337042}, url={http://dx.doi.org/10.1109/apec.1997.581483}, DOI={10.1109/apec.1997.581483}, booktitle={Proceedings of APEC 97 - Applied Power Electronics Conference}, publisher={IEEE}, author={Bowers, J.S. and Hopkins, D.C. and Sarjeant, W.J.}, year={2002}, month={Nov} } @inproceedings{bowers_hopkins_sarjeant_2002, title={Power packaging of a 12 kV, 240°C passive electronic module}, ISBN={0780343409}, url={http://dx.doi.org/10.1109/apec.1998.647736}, DOI={10.1109/apec.1998.647736}, booktitle={APEC '98 Thirteenth Annual Applied Power Electronics Conference and Exposition}, publisher={IEEE}, author={Bowers, J.S. and Hopkins, D.C. and Sarjeant, W.J.}, year={2002}, month={Nov} } @inproceedings{hopkins_root_2002, title={Synthesis of a new class of converters that utilize energy recirculation}, ISBN={0780318595}, url={http://dx.doi.org/10.1109/pesc.1994.373830}, DOI={10.1109/pesc.1994.373830}, booktitle={Proceedings of 1994 Power Electronics Specialist Conference - PESC'94}, publisher={IEEE}, author={Hopkins, D.C. and Root, D.W.}, year={2002}, month={Dec} } @inbook{hopkins_2001, place={San Diego, CA}, title={Packaging and Smart Power Systems}, booktitle={Power electronics handbook}, publisher={Academic Press}, author={Hopkins, D.C.}, editor={Rashid, M.H.Editor}, year={2001} } @inproceedings{bowers_hopkins_sarjeant_2000, title={Packaging Factors for Next Generation High Voltage, High Temperature Power Electrons Modules}, author={Bowers, J.S. and Hopkins, D.C. and Sarjeant, W.J.}, year={2000}, month={Jul} } @inproceedings{hopkins_o’mathuna_alderman_1998, title={A Four-Dimensional Road-Mapping Framework for Power Packaging Technology}, booktitle={Proceedings of the 1998 IMAPS International Symposium on Microelectronics}, author={Hopkins, D. C. and O’Mathuna, S. C. and Alderman, A.N.}, year={1998} } @article{hopkins_pitarressi_karker_1998, title={Systems Design Considerations for Using a Direct-Attached-Ceramic MMC Power Package}, journal={international journal on microelectronics reliability}, author={Hopkins, D.C. and Pitarressi, J.M. and Karker, J.A.}, year={1998} } @article{hopkins_pitarressi_1998, title={Thermal Impedance and Induced Stress in a Power Package Due to Variation in Layer Thickness}, journal={International Journal of Microcircuits and Electronic Packaging}, author={Hopkins, D.C. and Pitarressi, J.M.}, year={1998} } @article{hopkins_1997, place={Reston, VA}, title={Power Electronics Packaging}, volume={24}, number={1}, journal={Advancing Microelectronics Magazine}, publisher={International Microelectronics and Packaging Society}, author={Hopkins, D.C.}, year={1997}, month={Jan}, pages={10} } @inproceedings{hopkins_pitarressi_karker_1997, place={SPIE}, title={Thermal Impedance and Stress in a Power Package Due to Variations in Layer Thickness}, volume={3235}, booktitle={SPIE Proceedings Series}, publisher={Bellingham, Washington}, author={Hopkins, D.C. and Pitarressi, J.M. and Karker, J.A.}, year={1997}, month={Oct}, pages={72–77} } @book{hopkins_1996, title={High Temperature Capacitors}, institution={Custom Electronics Inc}, author={Hopkins, D.C.}, year={1996}, month={Apr} } @book{hopkins_1996, title={Investigation of a Power Package Incorporating a Direct Attached Ceramic/AlSiC Structure}, institution={BrushWellman Incorporated}, author={Hopkins, D.C.}, year={1996}, month={Jan} } @inproceedings{hopkins_pitarressi_fridline_karker_1996, title={System Design Considerations for using a Direct–Attached–Ceramic MMC Power Package}, booktitle={Proceedings of 32nd International Power Conversion Conference}, author={Hopkins, D.C. and Pitarressi, J.M. and Fridline, D.R. and Karker, J.A.}, year={1996}, pages={683–690} } @book{hopkins_1995, title={Assessment of the Power Conversion Thrust Area}, institution={Lawrence Livermore National Laboratory}, author={Hopkins, D.C.}, year={1995}, month={Jul} } @book{hopkins_1995, title={Cost Estimate for the ARM Electronic Circuit Cards}, institution={Lawrence Livermore National Laboratory}, author={Hopkins, D.C.}, year={1995}, month={Nov} } @inproceedings{hopkins_sarkar_1994, title={A mathematical approach to minimize the total mass of a space based power system by using multivariable non-linear optimization}, url={http://dx.doi.org/10.2514/6.1994-3807}, DOI={10.2514/6.1994-3807}, booktitle={Intersociety Energy Conversion Engineering Conference}, publisher={American Institute of Aeronautics and Astronautics}, author={Hopkins, Douglas and Sarkar, Madhushree}, year={1994}, month={Aug} } @inproceedings{hopkins_revis_1994, title={Development of a Three Dimensional Power Circuit Package for Aircraft Applications}, booktitle={1994 Proceedings: International Symposium on Microelectronics}, author={Hopkins, D.C. and Revis, R.}, year={1994}, pages={124–128} } @article{hopkins_bhavnani_1994, title={Optimizing Conductor Thickness in Power Hybrid Circuits}, number={3rd Quarter}, journal={International Journal of Microcircuits and Electronic Packaging}, author={Hopkins, D.C. and Bhavnani, S.H.}, year={1994}, pages={293–301} } @inproceedings{hopkins_bhavnani_1993, title={Determining Conductor Thickness in Power Circuits that Operate at Long Wavelength Frequencies}, booktitle={Proceedings of the 1993 ISHM Intternational Symposium on Microelectronics}, author={Hopkins, D.C. and Bhavnani, S.H.}, year={1993}, pages={656–661} } @article{hopkins_mosling_hung_1993, title={Dynamic equalization during charging of serial energy storage elements}, volume={29}, ISSN={0093-9994}, url={http://dx.doi.org/10.1109/28.216545}, DOI={10.1109/28.216545}, number={2}, journal={IEEE Transactions on Industry Applications}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Hopkins, D.C. and Mosling, C.R. and Hung, S.T.}, year={1993}, pages={363–368} } @article{hopkins_bhavnani_dalal_1993, title={Effect of Metallization Thickness on Thermal Conductance of a First-Level Power Hybrid Structure}, number={2nd Quarter}, journal={International Journal of Microcircuits and Electronic Packaging}, author={Hopkins, D.C. and Bhavnani, S.H. and Dalal, K.H.}, year={1993}, pages={189–193} } @article{hung_hopkins_mosling_1993, title={Extension of battery life via charge equalization control}, volume={40}, ISSN={0278-0046}, url={http://dx.doi.org/10.1109/41.184826}, DOI={10.1109/41.184826}, number={1}, journal={IEEE Transactions on Industrial Electronics}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Hung, S.T. and Hopkins, D.C. and Mosling, C.R.}, year={1993}, pages={96–104} } @book{hopkins_1993, title={High Density Shunt Regulator Development}, institution={Martin Marietta Corporation}, author={Hopkins, D.C.}, year={1993}, month={Dec} } @book{hopkins_1993, title={Investigation of High Frequency Resonant Effects in Batteries}, institution={NASA Lewis Research Center}, author={Hopkins, D.C.}, year={1993}, month={Aug} } @book{hopkins_1993, title={Systems Engineering of Shared Resources: Decision Support System for the Concept Definition Phases}, journal={NASA-OAI Collaborative Aerospace Research and Fellowship Program at Lewis Research Center}, institution={Lewis Research Center}, author={Hopkins, D.C.}, year={1993}, pages={25–26} } @book{systems engineering of shared resources: decision support for the concept design phase – modeling development_1993, institution={NASA Lewis Research Center}, year={1993}, month={Dec} } @book{hopkins_1992, title={Materials Support for the Investigation of Charge Equalization in Serial Batteries}, number={NAG8-123}, author={Hopkins, D.C.}, year={1992}, pages={VII–1 – VII-21} } @inproceedings{hopkins_bhavnani_dalal_1992, title={Numerical Modeling and Experimental Comparison of Copper Bonded AlN, Al2O3 and BeO Power Hybrid Structures}, booktitle={Proceedings of the 1992 International Electronics Packaging Conference}, author={Hopkins, D.C. and Bhavnani, S.H. and Dalal, K.H.}, year={1992} } @book{hopkins_1992, title={Power Measurement in Converters}, institution={NASA Lewis Research Center}, author={Hopkins, D.C.}, year={1992}, month={Aug} } @inproceedings{hopkins_bhavnani_dalal_1992, title={Thermal Performance Comparison and Metallurgy of Direct Copper Bonded AlN, Al2O3 and BeO Assemblies}, booktitle={Proceedings of the 1992 ISHM International Symposium on Microelectronics}, author={Hopkins, D.C. and Bhavnani, S.H. and Dalal, K.H.}, year={1992}, pages={577–583} } @book{hopkins_1991, title={Optimum Operating Temperature for a Minimum Mass Space Power System}, institution={NASA Lewis Research Center}, author={Hopkins, D.C.}, year={1991}, month={Aug} } @inproceedings{hopkins_mosling_hung_1991, title={The use of equalizing converters for serial charging of long battery strings}, ISBN={0780300246}, url={http://dx.doi.org/10.1109/apec.1991.146221}, DOI={10.1109/apec.1991.146221}, booktitle={[Proceedings] APEC '91: Sixth Annual Applied Power Electronics Conference and Exhibition}, publisher={IEEE}, author={Hopkins, D.C. and Mosling, C.R. and Hung, S.T.}, year={1991} } @book{hopkins_1990, title={Current Limiting Remote Power Control Module}, number={NGT-01-002-009}, institution={NASA Marshal Space Flight Center}, author={Hopkins, D.C.}, year={1990}, month={Sep} } @article{hopkins_1989, title={Designing Hybrid Power Supplies}, volume={5}, number={6}, journal={Powertechnics Magazine}, author={Hopkins, D.C.}, year={1989}, month={Jun}, pages={31–34} } @article{jovanovic_hopkins_lee_1989, title={Evaluation and design of megahertz-frequency off-line zero-current-switched quasi-resonant converters}, volume={4}, ISSN={0885-8993 1941-0107}, url={http://dx.doi.org/10.1109/63.21882}, DOI={10.1109/63.21882}, number={1}, journal={IEEE Transactions on Power Electronics}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Jovanovic, M.M. and Hopkins, D.C. and Lee, F.C.Y.}, year={1989}, month={Jan}, pages={136–146} } @book{hopkins_1989, title={High Density Power Transformer}, institution={Unisys Corporation}, author={Hopkins, D.C.}, year={1989}, month={Dec} } @book{hopkins_lee_1989, title={High-Performance, High-Frequency, Distributed, Computer Power Supply Technology}, institution={Digital Equipment Corporation}, author={Hopkins, D.C. and Lee, F.C.}, year={1989}, month={Jun} } @article{hopkins_jovanovic_lee_stephenson_1989, title={Hybridized off-line 2-MHz zero-current-switched quasi-resonant converter}, volume={4}, ISSN={0885-8993 1941-0107}, url={http://dx.doi.org/10.1109/63.21883}, DOI={10.1109/63.21883}, number={1}, journal={IEEE Transactions on Power Electronics}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Hopkins, D.C. and Jovanovic, M.M. and Lee, F.C.Y. and Stephenson, F.W.}, year={1989}, month={Jan}, pages={147–154} } @article{johnson_weeks_hopkins_muir_williams_1989, title={Plated copper on ceramic substrates for power hybrid circuits}, volume={12}, ISSN={0148-6411}, url={http://dx.doi.org/10.1109/33.49011}, DOI={10.1109/33.49011}, number={4}, journal={IEEE Transactions on Components, Hybrids, and Manufacturing Technology}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Johnson, R.W. and Weeks, R. and Hopkins, D.C. and Muir, J. and Williams, J.R.}, year={1989}, pages={530–536} } @inproceedings{hopkins_jovanovic_lee_stephenson_1989, title={Power-Hybrid Design of a High-Frequency ZCS-QRC}, booktitle={Proceedings of the Fourth Annual High Frequency Power Conversion Conference}, author={Hopkins, D.C. and Jovanovic, M.M. and Lee, F.C. and Stephenson, F.W.}, year={1989}, pages={304–317} } @book{hopkins_1989, title={Testing of High Power Devices}, number={LABCOM-ETDL, DAAL03-86-D-001, DO 1576}, institution={U.S. Army}, author={Hopkins, D.C.}, year={1989}, month={Sep} } @inproceedings{hopkins_1989, title={The Effects of Power Hybridization on Power Electronic Circuits}, booktitle={ISHM International Symposium on Microelectronics Proceedings}, author={Hopkins, D.C.}, year={1989}, month={Oct}, pages={647–654} } @inproceedings{johnson_hopkins_jaeger_1989, title={The Microelectronics Program at Auburn University}, booktitle={ISHM International Symposium on Microelectronics Proceedings}, author={Johnson, R.W. and Hopkins, D.C. and Jaeger, R.C.}, year={1989}, month={Oct}, pages={367–375} } @article{hopkins_1989, title={Thick-Film Technique Helps Hybridized, 2 MHz ZC-QR Converter Achieve 78% Efficiency}, volume={15}, number={7}, journal={Power Conversion & Intelligent Motion}, author={Hopkins, D.C.}, year={1989}, month={Jul}, pages={57–66} } @inproceedings{hopkins_1989, title={Thick-film power hybridization of switchmode power circuits}, url={http://dx.doi.org/10.1109/apec.1989.36977}, DOI={10.1109/apec.1989.36977}, booktitle={Proceedings, Fourth Annual IEEE Applied Power Electronics Conference and Exposition}, publisher={IEEE}, author={Hopkins, D.C.}, year={1989} } @inproceedings{hopkins_stephenson_lee_1988, title={Determination of Conductor Thickness and Width for Power-Hybrid Circuits}, booktitle={Proceedings of the Sixth Annual Power Electronics Seminar}, author={Hopkins, D.C. and Stephenson, F.W. and Lee, F.C.}, year={1988}, pages={71–83} } @phdthesis{hopkins_1988, title={Development of a High-Density, Off-Line, Quasi-Resonant Converter Using Hybrid Techniques}, school={Virginia Polytechnic Institute and State University}, author={Hopkins, D.C.}, year={1988} } @book{hopkins_lee_1988, title={High-Performance, High-Frequency, Distributed, Computer Power Supply Technology}, institution={Digital Equipment Corporation}, author={Hopkins, D.C. and Lee, F.C.}, year={1988}, month={Feb} } @inproceedings{hopkins_stephenson_lee_1988, title={Off-Line ZCS-QRC Thick-Film Hybrid Circuit}, booktitle={Proceedings of the Sixth Annual Power Electronics Seminar}, author={Hopkins, D.C. and Stephenson, F.W. and Lee, F.C.}, year={1988}, pages={71–83} } @inproceedings{hopkins_stephenson_lee_1988, title={Printing of Thick Thick-Film Conductors for Power Hybrid Circuits}, booktitle={ISHM International Symposium on Microelectronics Proceedings}, author={Hopkins, D.C. and Stephenson, F.W. and Lee, F.C.}, year={1988}, month={Oct}, pages={95–101} } @inproceedings{jovanovic_hopkins_lee_1987, title={Design Aspects for High-Frequency Off-Line Quasi-Resonant Converter}, booktitle={Proceedings of the Second Annual High Frequency Power Conversion Conference}, author={Jovanovic, M.M. and Hopkins, D.C. and Lee, F.C.}, year={1987}, month={Apr}, pages={83–97} } @book{hopkins_lee_1987, title={High-Performance, High-Frequency, Distributed, Computer Power Supply Technology}, institution={Digital Equipment Corporation}, author={Hopkins, D.C. and Lee, F.C.}, year={1987}, month={Feb} } @inproceedings{hopkins_jovanovicm_lee_stephenson_1987, title={Two-megahertz off-line hybridized quasi-resonant converter}, url={http://dx.doi.org/10.1109/apec.1987.7067139}, DOI={10.1109/apec.1987.7067139}, booktitle={1987 IEEE Applied Power Electronics conference and Exposition}, publisher={IEEE}, author={Hopkins, D.C. and Jovanovicm, M.M. and Lee, F.C. and Stephenson, F.W.}, year={1987}, month={Mar} } @inproceedings{hopkins_jovanovic_stephenson_lee_1986, title={One-Megahertz, Off-Line Converter Hybridization}, booktitle={Proceedings of the Fourth Annual Power Electronics Seminar}, author={Hopkins, D.C. and Jovanovic, M.M. and Stephenson, F.W. and Lee, F.C.}, year={1986}, pages={134–148} } @book{hopkins_lee_1985, title={Evaluation of Semiconductor Devices for Electric and Hybrid Vehicles (EHV) AC-Drive Applications,}, number={JPL9950-1038}, institution={Department of Energy and Jet Propulsion Laboratory}, author={Hopkins, D.C. and Lee, F.C.}, year={1985}, month={May} } @book{hopkins_lee_1985, title={Very High Frequency Quasi-Resonant Converters for Use in High Density Power Supplies for Military Applications}, institution={Texas Instruments Inc}, author={Hopkins, D.C. and Lee, F.C.}, year={1985}, month={Dec} } @inproceedings{hopkins_1984, title={Status of Power Devices, IC's and Support Chips}, booktitle={Proceedings of the Second Annual Power Electronics Seminar}, author={Hopkins, D.C.}, year={1984}, pages={2–9} } @inproceedings{hopkins_1983, title={Status of Semiconductor Power Switching Devices}, booktitle={Proceedings of the First Annual Power Electronics Seminar}, author={Hopkins, D.C.}, year={1983}, pages={82–91} } @article{steigerwald_hopkins_1981, title={Characteristic Input Harmonics of DC-DC Converters and their Effect on Input Filter Design}, volume={IECI-28}, ISSN={0018-9421}, url={http://dx.doi.org/10.1109/tieci.1981.351029}, DOI={10.1109/tieci.1981.351029}, number={2}, journal={IEEE Transactions on Industrial Electronics and Control Instrumentation}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Steigerwald, Robert L. and Hopkins, Douglas C.}, year={1981}, month={May}, pages={73–82} } @inproceedings{weeks_johnson_hopkins_muir_williams_1969, title={Plated copper on ceramic for power hybrid applications}, url={http://dx.doi.org/10.1109/ecc.1989.77803}, DOI={10.1109/ecc.1989.77803}, booktitle={Proceedings., 39th Electronic Components Conference}, publisher={IEEE}, author={Weeks, R. and Johnson, R.W. and Hopkins, D. and Muir, J. and Williams, J.R.}, year={1969} } @inproceedings{ye_basaran_hopkins, title={Pb Phase Growth in Eutectic Pb/Sn Flip Chip Solder Joint under Current Stressing”}, booktitle={Proceedings of 2003 Mechanics and Materials Conference}, author={Ye, H. and Basaran, C. and Hopkins, D.C.} }