@article{vergara_lunardi_2021, title={Fabrication of an Electrostatic Actuated Dielectric Mirror With Free-Standing Layers of Polymer}, volume={68}, ISSN={["1557-9646"]}, url={https://doi.org/10.1109/TED.2021.3116922}, DOI={10.1109/TED.2021.3116922}, abstractNote={Common materials used in dielectric mirrors are inorganic and rigid such that their optical properties cannot be modified. Here, we developed a method to fabricate a dielectric mirror with free-standing flexible layers that can be actuated by applying an electrostatic force or air pressure between the top and bottom ones. The membranes are sequentially compressed by reducing the structure reflectance by eliminating the air layers, where reflectance is the total electromagnetic power reflected divided in the incident one. A potential bias is applied between the layers of up to 30 V and an actuation time is shown to be less than 4.1 ms, recorded with a camera at 240 frames/s. Mirrors with length and width of up to $230~\mu \text{m}$ each were achieved with three polymer/air layers. The polymer free-standing layers thickness ranged from 840 to 1240 nm and the air gaps from 140 to 400 nm. The small gaps and the large length of the mirrors allow fast actuation with relatively low voltages. The mirrors can be designed to reflect specific colors of the visual spectrum with potential application for color reflective displays.}, number={12}, journal={IEEE TRANSACTIONS ON ELECTRON DEVICES}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Vergara, Pedro and Lunardi, Leda}, year={2021}, month={Dec}, pages={6240–6248} } @inbook{heterojunction bipolar transistors and monolithically integrated photoreceivers among other applications_2020, DOI={https://doi.org/10.1007/978-3-030-46377-9}, abstractNote={​This book contains stories and insight to women engineers’ contributions and research through the golden age of microelectronics, starting from the invention of the transistor in 1947 to modern day video games; while discussing the challenges they overcame.}, booktitle={Women in Microelectronics}, year={2020}, month={Jul} } @book{women in microelectronics_2020, url={http://www.springer.com/}, journal={Springer}, year={2020}, month={Jul} } @inproceedings{lunardi_cass_cimorelli_2018, title={Promoting academic and career success for raleigh future scholars at NC state university}, volume={2018-June}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85051175423&partnerID=MN8TOARS}, booktitle={ASEE Annual Conference and Exposition, Conference Proceedings}, author={Lunardi, L. and Cass, C. and Cimorelli, K.}, year={2018} } @inproceedings{vergara_lunardi_2017, title={Actuated polymer based dielectric mirror for visual spectral range applications}, volume={10354}, url={http://dx.doi.org/10.1117/12.2271871}, DOI={10.1117/12.2271871}, abstractNote={Miniature dielectric mirrors are useful components for lasers, thin film beam splitters and high quality mirrors in optics. These mirrors usually made from rigid inorganic materials can achieve a reflectance of almost one hundred percent. Being structural components, as soon as fabricated their reflectance and/or bandwidth remains constant. Here it is presented a novel fabrication process of a dielectric mirror based on free standing polymer layers. By applying an electrostatic force between the top and the bottom layers the reflectance can be changed. The large difference between the polymers refractive index and the air allows to achieve a reflectance of more than 85% using only six pairs of nanolayers. Preliminary simulations indicate an actuation speed of less than 1ms. Experimental optical characterization of fabricated structures agrees well with simulation results. Furthermore, structures can be designed to reflect a particular set of colors and/or isolated by using color filters, so a color pixel is fabricated, where the reflectance for each isolated color can be voltage controlled. Potential applications include an active component in a reflective screen display.}, booktitle={Nanoengineering: Fabrication, Properties, Optics, and Devices XIV}, author={Vergara, P.P. and Lunardi, Leda}, year={2017}, month={Aug} } @inproceedings{vergara_lunardi_2017, title={Actuated polymer based dielectric mirror for visual spectral range applications}, volume={10354}, booktitle={Nanoengineering: fabrication, properties, optics, and devices xiv}, author={Vergara, P. P. and Lunardi, L.}, year={2017} } @inproceedings{cass_lunardi_gordon_2017, title={Promoting academic and career success for Raleigh Future Scholars at NC State}, volume={2017-June}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85030554357&partnerID=MN8TOARS}, booktitle={ASEE Annual Conference and Exposition, Conference Proceedings}, author={Cass, C. and Lunardi, L. and Gordon, O.C.}, year={2017} } @article{mehta_borders_liu_pandey_datta_lunardi_2016, title={III-V Tunnel FET Model With Closed-Form Analytical Solution}, volume={63}, ISSN={["1557-9646"]}, url={http://dx.doi.org/10.1109/ted.2015.2471808}, DOI={10.1109/ted.2015.2471808}, abstractNote={Using an idealized semianalytical model of charge transport for InAs-based tunneling FET, it is shown that the output and transfer characteristics can be accurately reproduced and could be used to develop compact models. The use of a mathematical approximation for the analytical solution of the surface potential is vital here to minimize the computation time. The 20-nm gate homojunction and 40-nm gate heterojunction transistors have been simulated and compared with the calibrated numerical simulation results. The results are in good agreement.}, number={5}, journal={IEEE TRANSACTIONS ON ELECTRON DEVICES}, author={Mehta, J. U. and Borders, W. A. and Liu, H. and Pandey, R. and Datta, S. and Lunardi, L.}, year={2016}, month={May}, pages={2163–2168} } @inproceedings{mehta_lunardi_2015, title={Lateral silicon photodiodes with extremely low dark current for visible and infra-red applications}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84964890183&partnerID=MN8TOARS}, DOI={10.1109/ipcon.2015.7323594}, abstractNote={We present two lateral p-i-n photodiodes for operation in the 400-900nm wavelength range. The design is compatible with typical 180nm CMOS process and yields high responsivity and low dark current independent of the geometry.}, booktitle={2015 photonics conference (ipc)}, author={Mehta, J. and Lunardi, Leda}, year={2015}, pages={446–447} } @inproceedings{mehta_borders_lunardi_liu_datta_2014, title={A compact model for compound semiconductor tunneling field-effect-transistors}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84911966728&partnerID=MN8TOARS}, DOI={10.1109/SECON.2014.6950716}, abstractNote={This paper proposes a compact behavioral model for homojunction compound semiconductor-based tunneling field effect transistors. The approach used here consists of using equations derived from basic device physics used previously for similar silicon based transistors but modified for InAs materials and measured 20 nm gate length experimental device parameters. The results of the calculated output transfer characteristics agree well over a wide range of gate voltage values. The ultimate goal is to implement this model in a circuit simulator for designing and testing of tunneling field effect transistors (TFET)-based circuits for low power applications.}, booktitle={Conference Proceedings - IEEE SOUTHEASTCON}, author={Mehta, U. and Borders, W.A. and Lunardi, L. and Liu, H. and Datta, S.}, year={2014} } @inbook{lunardi_mokkapati_jagadish_2013, title={Optoelectronic Devices}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84986915862&partnerID=MN8TOARS}, DOI={10.1002/9781118517543.ch20}, abstractNote={This chapter covers the advances on semiconductor devices that manipulate light, convert photons to electrons, and their applications. Some devices are designed for generation of light. The materials used in all these devices have steered the applications from communications, to medical instrumentation, scanners, and consumer electronics in a way thatsemiconductor optoelectronics became ubiquitous.}, booktitle={Guide to State-of-the-Art Electron Devices}, author={Lunardi, L. and Mokkapati, S. and Jagadish, C.}, year={2013}, pages={265–274} } @inproceedings{lunardi_2013, title={Undergraduate research and the smart grid: REU-Site: Engineering the grid}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84884333631&partnerID=MN8TOARS}, booktitle={ASEE Annual Conference and Exposition, Conference Proceedings}, author={Lunardi, L.}, year={2013} } @inproceedings{sharma_oseroff_lunardi_2012, title={Intermetallic Formation in PZT for MEMS Structures}, volume={1427}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84879273166&partnerID=MN8TOARS}, DOI={10.1557/opl.2012.1404}, abstractNote={Crack free lead zirconate titanate (PZT) films for piezoelectric based MEMS devices have been prepared by a multiple coating sol gel process on platinized silicon (100) substrates. Rapid thermal annealing and Conventional furnace annealing were used for densification and crystallization of the amorphous PZT films. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Atomic force microscopy (AFM) were used to observe surface film morphology and grain growth. The phase content of the films was analyzed using X-ray diffraction. The role of intermetallics formed during the heat treatment in the growth of different orientations has also been observed. Film aging critical for device performance has been observed and methods to revert aging effects have been examined and discussed.}, booktitle={Materials Research Society Symposium Proceedings}, author={Sharma, K.P. and Oseroff, T. and Lunardi, L.}, year={2012}, pages={56–61} } @article{tomkos_mukherjee_korotky_tucker_lunardi_2012, title={The Evolution of Optical Networking}, volume={100}, ISSN={["0018-9219"]}, url={http://dx.doi.org/10.1109/jproc.2012.2187363}, DOI={10.1109/jproc.2012.2187363}, abstractNote={In 2010, the scientific and engineering communities celebrated the 50th anniversary of the first demonstration of the laser, the 40th anniversary of the first demonstration of a low-loss optical fiber, and the Nobel Prize award to Dr. Charles Cao, who first proposed silica as a practical material for longdistance optical fiber communication. These innovations facilitated the optical telecommunications revolution that started in the mid-1970s and continues today. From the first pointto-point fiber optic connections at megabit per second rates over several kilometers to today’s multiterabit ultralong-haul dense wavelengthdivision multiplexed systems, optical communication networks have experienced remarkable year over year increases in productivity, as measured by capacity growth, cost reduction, and increased automation and flexibility. In addition to the aforementioned milestones, we decided to organize a special issue on the BEvolution of Optical Networking[ to celebrate the centennial anniversary of the Proceedings of the IEEE marking the aforementioned occasions but also the impact and enhanced quality of life that optical networking has brought to our society. Today, the term Boptical networks[ denotes high-capacity telecommunications networks based on optical technologies and components that can provide capacity, provisioning, routing, grooming, or restoration at the wavelength level. It is well understood and appreciated that optical networking through the increased capacity it offers at a reduced cost per transmitted bit per kilometer compared to other long-distance Digital Object Identifier: 10.1109/JPROC.2012.2187363 The topics of this special issue cover the evolution of the optical networking solutions that have shown the greatest impact over the past years and the largest potential for the future, and include topics from optical network technologies to optical network architecture, algorithms and protocols, from core to access network segments.}, number={5}, journal={PROCEEDINGS OF THE IEEE}, author={Tomkos, Ioannis and Mukherjee, Biswanath and Korotky, Steven K. and Tucker, Rodney S. and Lunardi, Leda}, year={2012}, month={May}, pages={1017–1022} } @article{luo_wellenius_lunardi_muth_2012, title={Transparent IGZO-Based Logic Gates}, volume={33}, ISSN={["1558-0563"]}, url={http://dx.doi.org/10.1109/led.2012.2186784}, DOI={10.1109/led.2012.2186784}, abstractNote={Optically transparent indium-gallium-zinc-oxide-based nand and nor gates and inverters were fabricated and characterized using transistors deposited at room temperature with 5-, 10-, and 20-μm gate lengths and beta ratio between 2.5 and 40. The nand and nor gates' operation frequencies were measured up to 5 kHz. The individual transistors were measured to have saturation mobility of 14 cm2/V ·s, subthreshold swing of 190 mV/dec, and current on/off ratios in excess of 108. Logic operations were satisfactorily demonstrated for bias voltage between 1 and 20 V. These results indicate that viable digital logic can be applied particularly where optical transparency or the use of novel flexible substrates is more important than the operating speeds.}, number={5}, journal={IEEE ELECTRON DEVICE LETTERS}, author={Luo, Haojun and Wellenius, Patrick and Lunardi, Leda and Muth, John F.}, year={2012}, month={May}, pages={673–675} } @article{morgensen_lunardi_2011, title={Analytical Correction for Effective Mobility Measurements in MOSFETs}, volume={58}, ISSN={["0018-9383"]}, url={http://dx.doi.org/10.1109/ted.2011.2158581}, DOI={10.1109/ted.2011.2158581}, abstractNote={Differences in drain bias used for the capacitance and current measurement steps can lead to inaccuracy in the extraction of mobility at low fields. An analytical correction for a bulk MOSFET can be applied to the capacitance measurement to correct for the effect of drain bias provided doping and oxide capacitance density are known. The proposed correction successfully corrects measured mobility data and is proven by comparison with results obtained from an improved but experimentally more complicated technique.}, number={9}, journal={IEEE TRANSACTIONS ON ELECTRON DEVICES}, author={Morgensen, Michael P. and Lunardi, Leda M.}, year={2011}, month={Sep}, pages={2871–2873} } @inproceedings{luo_wellenius_lunardi_muth_2010, title={Amorphous InGaZnO logic gates for transparent electronics}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77957605970&partnerID=MN8TOARS}, DOI={10.1109/DRC.2010.5551866}, abstractNote={InGaZnO is an amorphous oxide semiconductor with electron mobility an order of magnitude higher than that of amorphous silicon or organic semiconductors. The ability to control carrier concentration, the wide band gap and deposition at room temperature make it an excellent candidate for transparent electronic systems on glass or plastics. Thus far, most reports have focused on the performance of the performance of single discrete devices [1],[2] or simple ring oscillator circuits operating at 2 MHz [3]. While a OR gate has recently been published [4] operating at10 Hz, in general the basic building blocks for transparent digital logic has not been investigated. In this paper we present, transparent logic showing good performance from inverters, NAND and NOR gates, all deposited at room temperature. The significance of these results is that construction of these basic digital logic building blocks with high gain and fast response demonstrate the viability for amorphous oxide digital logic to be utilized in transparent, and flexible electronic systems.}, booktitle={Device Research Conference - Conference Digest, DRC}, author={Luo, H. and Wellenius, P. and Lunardi, L. and Muth, J.F.}, year={2010}, pages={121–122} } @article{lou_lunardi_muth_2010, title={Fabrication of Nanoshell Arrays Using Directed Assembly of Nanospheres}, volume={10}, ISSN={["1558-1748"]}, url={http://dx.doi.org/10.1109/jsen.2009.2038586}, DOI={10.1109/jsen.2009.2038586}, abstractNote={Extraordinary transmission of light has been observed when light is incident on periodic nanostructures patterned metal films, which results from the interaction between the incident photons and the excited surface plasmon polaritons with wavenumbers constrained by the geometry and periodicity of the surface structure. Usually, the surface patterns are fabricated by Focused Ion Beam (FIB) milling, which is expensive and has low throughput. We employ the nanosphere lithography method to fabricate periodic nanoshell arrays on a gold film as an alternative to FIB milling. In this process, polystyrene nanospheres are deposited on glass substrates as a template for subsequent gold deposition. This results in the close-packed hexagonal nanoshell arrays patterned gold surface. The transmission spectra of the patterned surfaces show strong enhanced transmission in the red and IR wavelength regions, and the peak enhanced transmission wavelengths vary with the chemical environments above the surface.}, number={3}, journal={IEEE SENSORS JOURNAL}, author={Lou, Yi and Lunardi, Leda M. and Muth, John F.}, year={2010}, month={Mar}, pages={617–620} } @article{suresh_wellenius_baliga_luo_lunardi_muth_2010, title={Fast All-Transparent Integrated Circuits Based on Indium Gallium Zinc Oxide Thin-Film Transistors}, volume={31}, ISSN={["1558-0563"]}, url={http://dx.doi.org/10.1109/led.2010.2041525}, DOI={10.1109/led.2010.2041525}, abstractNote={We describe the fabrication and characterization of visible transparent small-scale indium gallium zinc oxide (IGZO) integrated circuits. The IGZO channel and indium tin oxide (ITO) contacts and interconnects were pulsed laser deposited at room temperature. Low-temperature (200 °C ) atomic-layer-deposited Al2O3 was used as the gate dielectric in bottom-gated thin-film transistors with field-effect mobility near 15 cm2/V·s. Logic inverters and ring oscillators were fabricated and characterized, with operations at frequencies as high as 2.1 MHz, corresponding to a propagation delay of less than 48 ns/stage with a supply voltage of 25 V. To the best of our knowledge, these are the fastest all-transparent oxide semiconductor circuits reported to date.}, number={4}, journal={IEEE ELECTRON DEVICE LETTERS}, author={Suresh, Arun and Wellenius, Patrick and Baliga, Vinay and Luo, Haojun and Lunardi, Leda M. and Muth, John F.}, year={2010}, month={Apr}, pages={317–319} } @article{kumar_lunardi_meneghesso_pearton_schubert_2010, title={Guest Editorial Special Issue on Light-Emitting Diodes}, volume={57}, url={http://dx.doi.org/10.1109/ted.2009.2035570}, DOI={10.1109/ted.2009.2035570}, abstractNote={There are eight invited papers and 12 contributed papers in this special issue on light-emitting diodes.}, number={1}, journal={IEEE Transactions on Electron Devices}, author={Kumar, M.J. and Lunardi, L. and Meneghesso, G. and Pearton, S.J. and Schubert, E.F.}, year={2010}, month={Jan}, pages={7–11} } @article{kumar_lunardi_meneghesso_pearton_schubert_2010, title={Special issue on light-emitting diodes}, volume={57}, number={1}, journal={IEEE Transactions on Electron Devices}, author={Kumar, M. J. and Lunardi, L. and Meneghesso, G. and Pearton, S. J. and Schubert, E. F.}, year={2010}, pages={7–11} } @article{wellenius_suresh_luo_lunardi_muth_2009, title={An Amorphous Indium-Gallium-Zinc-Oxide Active Matrix Electroluminescent Pixel}, volume={5}, ISSN={["1558-9323"]}, url={http://dx.doi.org/10.1109/jdt.2009.2024012}, DOI={10.1109/JDT.2009.2024012}, abstractNote={In this study, an active matrix pixel was fabricated and characterized using indium gallium zinc oxide (IGZO) thin-film transistors and a novel electroluminescent (EL) Eu:IGZO thin-film phosphor. The results show that even large and unoptimized IGZO devices are capable of modulating at the frequencies necessary for modern display technology. Furthermore, we demonstrate a rare-earth doped amorphous-oxide semiconductor (AOS) EL phosphor that can be modulated via a TFT.}, number={12}, journal={JOURNAL OF DISPLAY TECHNOLOGY}, author={Wellenius, Patrick and Suresh, Arun and Luo, Haojun and Lunardi, Leda M. and Muth, John F.}, year={2009}, month={Dec}, pages={438–445} } @inproceedings{chintapatla_muth_lunardi_2009, title={Controlling the wrinkling of the bilayer thin films electrothermally}, volume={1139}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-70449574600&partnerID=MN8TOARS}, booktitle={Materials Research Society Symposium Proceedings}, author={Chintapatla, S. and Muth, J.F. and Lunardi, L.M.}, year={2009}, pages={97–102} } @inproceedings{shelton_muth_holland_lunardi_2006, title={Characterization of silicon nitride micromachined beams via remote optical interrogation}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-41549133186&partnerID=MN8TOARS}, DOI={10.1109/omems.2006.1708303}, abstractNote={We demonstrate that mechanical characterization of the motion of micromachined double- clamped silicon nitride beams is possible via remote optical interrogation. Using Fabry-Perot interferometry, information about the absolute displacement and resonant frequency of various mechanical modes is determined}, booktitle={IEEE/LEOS International Conference on Optical MEMS and Their Applications Conference, 2006}, author={Shelton, W.A. and Muth, J.F. and Holland, J.L. and Lunardi, L.M.}, year={2006}, pages={138–139} } @article{gollakota_dhawan_wellenius_lunardi_muth_saripalli_peng_everitt_2006, title={Optical characterization of Eu-doped β-Ga2O3 thin films}, volume={88}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.2208368}, DOI={10.1063/1.2208368}, abstractNote={Europium-doped β-Ga2O3 thin films were grown on double-side polished c-axis (0001) sapphire substrates by pulsed laser deposition at 850°C. Transmission measurements of the films revealed a sharp band edge with a band gap at 5.0eV. The films exhibited intense red emission at 611nm (2.03eV) due to the transitions from D05 to F27 levels in europium, with intensities that increased with the concentration of europium. Time-resolved photoluminescence measurements revealed a temperature-insensitive lifetime of 1.4ms, which is much longer than the lifetimes of europium luminescence observed in GaN hosts.}, number={22}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Gollakota, P. and Dhawan, A. and Wellenius, P. and Lunardi, L. M. and Muth, J. F. and Saripalli, Y. N. and Peng, H. Y. and Everitt, H. O.}, year={2006}, month={May}, pages={221906} } @inproceedings{muth_gollakota_dhawan_porter_saripalli_lunardi_2005, title={Gallium Oxide as a host for rare earth elements}, volume={866}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-30544448982&partnerID=MN8TOARS}, DOI={10.1557/proc-866-v6.2}, abstractNote={Pulsed Electron Beam Deposition (PEBD) and Pulsed Laser Deposition (PLD) were used to grow Gallium Oxide (Ga2O3) thin films on double sided polished sapphire substrates. At 850 o C substrate temperature, smooth single crystal β-Ga2O3 films were obtained, which were confirmed with measurements by AFM of RMS surface roughness of about 1 nm. When characterized under electron beam excitation, the films exhibited different responses. For example: Europium doped films emitted intense red emission from 5 D0 to 7 Fj transitions while exhibiting weak broad emission from 300 to 500 nm. In contrast, Erbium doped films emitted strong emission from 300 to 500 nm peaked at 360 nm that was attributed to defects in the host matrix. Green emission from the Erbium transitions was observed at 528 and 550 nm. Films with different rare earth compositions varying from 0.1 % to 0.4 % were also prepared. High quality natural waveguides were formed with the deposited Ga2O3 films on the lower refractive index substrate sapphire. This was confirmed by measuring the refractive index by prism coupling and sharp coupling spectra.}, booktitle={Materials Research Society Symposium Proceedings}, author={Muth, J.F. and Gollakota, P. and Dhawan, A. and Porter, H.L. and Saripalli, Y.N. and Lunardi, L.M.}, year={2005}, pages={177–182} } @inproceedings{lunardi_welser_2003, title={Plenary session}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0842288304&partnerID=MN8TOARS}, booktitle={Technical Digest - International Electron Devices Meeting}, author={Lunardi, L. and Welser, J.}, year={2003}, pages={1} } @inproceedings{moss_lunardi_lamont_randall_colbourne_chandrasekhar_buhl_hulse_2003, title={Tunable Dispersion Compensation at 10Gb/s and 40Gb/S Using Multicavity All-Pass Etalons}, volume={86}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-1642524225&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Moss, D. and Lunardi, L. and Lamont, M. and Randall, G. and Colbourne, P. and Chandrasekhar, S. and Buhl, L. and Hulse, C.}, year={2003}, pages={162–163} } @inproceedings{lunardi_welser_candelaria_2003, title={Welcome from the general chair}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0842266682&partnerID=MN8TOARS}, booktitle={Technical Digest - International Electron Devices Meeting}, author={Lunardi, L. and Welser, J. and Candelaria, J.}, year={2003} } @inproceedings{chen_pavlik_visone_pan_gonzales_turukhin_lunardi_al-salameh_lumish_2002, title={40 nm broadband SOA-Raman hybrid amplifier}, volume={70}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0036438676&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Chen, Y. and Pavlik, R. and Visone, C. and Pan, F. and Gonzales, E. and Turukhin, A. and Lunardi, L. and Al-Salameh, D. and Lumish, S.}, year={2002}, pages={390–391} } @article{desalvo_wilson_rollman_schneider_lunardi_lumish_agrawal_steinbach_baun_wall_et al._2002, title={Advanced components and sub-system solutions for 40 Gb/s transmission}, volume={20}, url={http://dx.doi.org/10.1109/jlt.2002.806782}, DOI={10.1109/jlt.2002.806782}, abstractNote={With the commissioning of the latest 10-Gb/s systems, vendors are now in the process of developing architectures for their next-generation products. 40-Gb/s components and subsystems are currently in development to address the necessities of these next-generation systems. The top three challenges associated with 40-Gb/s transmission are optical signal-to-noise ratio, dispersion, and high-speed components. In order to realize 40-Gb/s transmission, new component and subsystem developments are crucial. This paper reviews the latest transmission technologies and dispersion compensation techniques developed to fulfill 40-Gb/s transmission system requirements.}, number={12}, journal={Journal of Lightwave Technology}, author={DeSalvo, R. and Wilson, A.G. and Rollman, J. and Schneider, D.F. and Lunardi, L.M. and Lumish, S. and Agrawal, N. and Steinbach, A.H. and Baun, W. and Wall, T. and et al.}, year={2002}, month={Dec}, pages={2154–2181} } @inproceedings{chen_lunardi_al-salameh_lumish_2002, title={Raman tilt and nonideal tilt control function of C-band erbium-doped fiber amplifiers}, volume={4906}, url={http://dx.doi.org/10.1117/12.480569}, DOI={10.1117/12.480569}, abstractNote={Due to stimulated Raman scattering, shorter wavelength channels will pump longer wavelength channels, and so transfer their energy to longer wavelength channels. A tilt occurs when a flat DWDM signals travel through transmission fiber. We characterized the Raman tilt for 100 km SSMF and LEAF fiber at composite input powers ranging from 13 dBm to 22 dBm with a 40-channel laser source with 100 GHz spacing. Raman tilt with different fiber length at different composite launch power for SSMF is fully studied. In order to compensate the positive Raman gain tilt generated in the transmission fiber, a negative tilt is required. A tilt control function is available in some EDFAs. The mechanism of this tilt control is to use a tunable attenuator to change the internal loss of the amplifier. Unfortunately, the negatively tilted gain spectrum achieved by this mechanism is not a straight line. From the simulation result, the tilted gain curve actually can be regarded as two straight lines with a junction at about 1538 nm in good approximation. By combining the Raman output spectrum with the EDFA output spectrum, tilt is eliminated, but a non-flat spectral shape is generated with a dip at 1538 nm. This combined spectral shape agrees quite well with the measured spectral shape in actual system. This study reveals imperfection with this tilt compensation mechanism. A new tilt compensation solution is proposed and tested. Test results shown significant flatness improvement.}, booktitle={Optical Components and Transmission Systems}, author={Chen, Y. and Lunardi, L. and Al-Salameh, D. and Lumish, S.}, year={2002}, month={Aug}, pages={185–192} } @inproceedings{turukhin_lunardi_gonzales_vreeburg_2002, title={SOA characteristics for L-BAND system applications}, volume={3}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84949009348&partnerID=MN8TOARS}, booktitle={European Conference on Optical Communication, ECOC}, author={Turukhin, A. and Lunardi, L. and Gonzales, E. and Vreeburg, K.}, year={2002} } @inproceedings{lunardi_2002, title={Semiconductor devices for fiber optic communication systems}, volume={1}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84906688594&partnerID=MN8TOARS}, DOI={10.1109/MIEL.2002.1003154}, abstractNote={We review the state-of-the-art of heterojunction-based integrated circuit technologies that have potential applications for time division multiplexing (TDM) and wavelength division multiplexing (WDM) fiber optic communication systems.}, booktitle={2002 23rd International Conference on Microelectronics, MIEL 2002 - Proceedings}, author={Lunardi, L.M.}, year={2002}, pages={99–102} } @article{lunardi_moss_chandrasekhar_buhl_lamont_mclaughlin_randall_colbourne_kiran_hulse_2002, title={Tunable dispersion compensation at 40-Gb/s using a multicavity etalon all-pass filter with NRZ, RZ, and CS-RZ modulation}, volume={20}, url={http://dx.doi.org/10.1109/jlt.2002.806768}, DOI={10.1109/jlt.2002.806768}, abstractNote={We present a multichannel tunable dispersion compensator (TDC) based on multicavity all-pass etalons that is capable of operation at 40 Gb/s. The device has a tuning range of +200/-220 ps/nm with a group delay ripple < /spl plusmn/5 ps over a channel bandwidth of 80 GHz, an overall loss of < 5.2 dB, very low insertion loss ripple, and can operate on any channel on a 200-GHz grid over the C-band. In addition, we present system performance results at 40 Gb/s using NRZ, RZ, and CS-RZ modulation, compensating up to 45 km of nonzero dispersion shifted fiber (NZDSF). Our results show that this device introduces very little excess system penalty with signal frequency drifts of up to 20 GHz when operated near the center of its tuning range. For single channel experiments with fiber, the system penalty increase versus signal detuning is more significant, but can be reduced by dynamically optimizing the device dispersion during detuning. Finally, we demonstrate simultaneous compensation of 4 channels across the C-band over 25 km of NZDSF.}, number={12}, journal={Journal of Lightwave Technology}, author={Lunardi, L.M. and Moss, D.J. and Chandrasekhar, S. and Buhl, L.L. and Lamont, M. and McLaughlin, S. and Randall, G. and Colbourne, P. and Kiran, S. and Hulse, C.A.}, year={2002}, month={Dec}, pages={2136–2144} } @inproceedings{chen_singh_lunardi_lumish_achtenhagen_singh_inniss_2001, title={Bi-directionally pumped broadband Raman amplifier}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0035741267&partnerID=MN8TOARS}, booktitle={European Conference on Optical Communication, ECOC}, author={Chen, Y. and Singh, A. and Lunardi, L. and Lumish, S. and Achtenhagen, M. and Singh, R. and Inniss, D.}, year={2001}, pages={230–231} } @article{lunardi_feuer_chen_singh_pavlik_gonzales_visone_lumish_2001, title={Challenges in component testing for optical systems}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0035654323&partnerID=MN8TOARS}, DOI={10.1109/LEOS.2001.968928}, abstractNote={We discuss several examples that have been obtained from testing components in system-like conditions from our point of view as a component maker. First, we examine the conventional bidirectional transmission using interleaved signals for two directions within same band. One advantage of the bidirectional interleaving transmission, over separate band bidirectional transmission is the reduction of the four wave mixing phenomenon, which occurs between narrowly spaced copropagating adjacent channels, and is mitigated due to the copropagating channel space doubling. In both uni- and bidirectional cases, separate paths and amplifiers for the traffic in the two directions are used at the amplification nodes. This, in turn, is not cost effective, and if not properly filtered could easily form a loop for Rayleigh backscattering. This limitation is almost entirely removed with the development of a birefringent interleaver filter, which can be combined with a non-reciprocal birefringent filter to deliver near-complete blockage of backreflected channels. The resulting components (i.e., bidirectional isolator, bidirectional circulator, four-port interleaver) enable the use of standard unidirectional optical components to create bidirectional networks that deliver twice the spectral efficiency of unidirectional networks. We also illustrate some of the technical challenges that face the designer of 40 Gbit/s systems but can only be overcome with new types of components, such as tunable dispersion compensators and low dispersion components.}, journal={Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS}, author={Lunardi, L.M. and Feuer, M.D. and Chen, Y. and Singh, A. and Pavlik, R. and Gonzales, E. and Visone, C. and Lumish, S.}, year={2001}, pages={540–541} } @inproceedings{birk_lunardi_gnauck_schumacher_behammer_2000, title={10-Gbit/s RZ pulses using an all-silicon nonlinear transmission line integrated circuit}, volume={1}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0033645117&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Birk, Martin and Lunardi, Leda M. and Gnauck, Alan H. and Schumacher, Hermann and Behammer, Dag}, year={2000}, pages={248–250} } @article{datta_roenker_cahay_lunardi_2000, title={Analytical modeling of pnp InP/InGaAs heterojunction bipolar transistors}, volume={44}, url={http://dx.doi.org/10.1016/s0038-1101(00)00055-1}, DOI={10.1016/s0038-1101(00)00055-1}, abstractNote={Abstract Pnp InP/InGaAs heterojunction bipolar transistors have been modeled using a modified Gummel–Poon model, and the results are compared with experimental measurements and results from a commercial simulator. The model provides a good description of the transistor’s high frequency performance and describes the falloff in device performance at high current densities. The model overestimates the current gain at low current densities by neglecting hole recombination in the base side of the emitter–base space charge region.}, number={7}, journal={Solid-State Electronics}, author={Datta, S. and Roenker, K.P. and Cahay, M.M. and Lunardi, L.M.}, year={2000}, month={Jul}, pages={1331–1333} } @article{feuer_thomas_lunardi_2000, title={Backreflection and loss in single-fiber loopback networks}, volume={12}, url={http://dx.doi.org/10.1109/68.868023}, DOI={10.1109/68.868023}, abstractNote={We have studied the effects of network loss and back-reflections on single-fiber loopback transmission, in which a modulator replaces the optical source at the remote terminal. Combining a broad-band source at the host terminal with an amplified modulator at the remote terminal effectively suppresses the optical beat noise, allowing data transmission at 50 Mb/s with realistic loss budgets, even in the presence of Fresnel back-reflections as large as -15 dB.}, number={8}, journal={IEEE Photonics Technology Letters}, author={Feuer, M.D. and Thomas, M.A. and Lunardi, L.M.}, year={2000}, month={Aug}, pages={1106–1108} } @inproceedings{feuer_lam_lunardi_woodward_2000, title={Crosstalk in a metro-scale ring with passive optical add/drop}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0034481563&partnerID=MN8TOARS}, booktitle={Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS}, author={Feuer, Mark D. and Lam, Cedric F. and Lunardi, Leda M. and Woodward, Sheryl L.}, year={2000}, pages={694–695} } @article{lin_goldstein_lunardi_2000, title={Integrated signal monitoring and connection verification in MEMS optical crossconnects}, volume={12}, url={http://dx.doi.org/10.1109/68.853537}, DOI={10.1109/68.853537}, abstractNote={We propose and demonstrate integrated signal-monitoring and connection-verification schemes for microelectromechanical-system (MEMS) optical crossconnects. The schemes utilize monolithically integrated beamsplitters and hybrid-integrated photodetectors as output signal-monitoring modules. To achieve connection verification, on-chip micromirror dithering is employed to encode optical signals with pilot tones that are used only internally to the crossconnect. The approaches described offer a potentially compact means of implementing several critical network-management and surveillance features.}, number={7}, journal={IEEE Photonics Technology Letters}, author={Lin, L.Y. and Goldstein, E.L. and Lunardi, L.M.}, year={2000}, month={Jul}, pages={885–887} } @article{lunardi_1999, title={Heterostructure circuit applications in optical communications}, volume={43}, url={http://dx.doi.org/10.1016/s0038-1101(99)00112-4}, DOI={10.1016/s0038-1101(99)00112-4}, abstractNote={Abstract Remarkable progress has been made in practical use of high-speed heterostructure device technologies for communications. To further expand the possible applications, devices with higher performance or able to perform new functions are going to be key elements for future transmission systems. In this article, the status of high-speed integrated circuits targeted for either wavelength division multiplexing (WDM) or time division multiplexing (TDM) is reviewed.}, number={8}, journal={Solid-State Electronics}, author={Lunardi, L.}, year={1999}, month={Aug}, pages={1627–1632} } @inproceedings{lunardi_lin_golsdtein_1999, title={Micromachined optical crossconnects with integrated signal-monitoring functionality}, volume={4}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85024724850&partnerID=MN8TOARS}, DOI={10.1109/OFC.1999.766016}, abstractNote={We demonstrate a single-chip optical-crossconnect module with integrated signal-monitoring functions for fast mesh-network restoration. High speed photodetectors are integrated in hybrid form with free-space micromechanical structures to achieve good performance and connection-monitoring, potentially in a compact low-cost configuration.}, booktitle={OFC/IOOC 1999 - Optical Fiber Communication Conference and the International Conference on Integrated Optics and Optical Fiber Communication}, author={Lunardi, L.M. and Lin, L.Y. and Golsdtein, E.L.}, year={1999}, pages={128–130} } @inproceedings{lunardi_lin_goldstein_1999, title={Micromachined optical crossconnects with integrated signal-monitoring functionality}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0032638549&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Lunardi, L.M. and Lin, L.Y. and Goldstein, E.L.}, year={1999} } @inproceedings{lin_goldstein_lunardi_tkach_1999, title={Micromachined optical-switching technologies for WDM networks}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0032599069&partnerID=MN8TOARS}, booktitle={LEOS Summer Topical Meeting}, author={Lin, L.Y. and Goldstein, E.L. and Lunardi, L.M. and Tkach, R.W.}, year={1999}, pages={57–58} } @article{lin_goldstein_lunardi_tkach_1999, title={Optical crossconnects for high-capacity lightwave networks}, volume={8}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0004664608&partnerID=MN8TOARS}, number={1}, journal={Journal of High Speed Networks}, author={Lin, L.Y. and Goldstein, E.L. and Lunardi, L.M. and Tkach, R.W.}, year={1999}, pages={17–34} } @article{rios_lunardi_chandrasekhar_miyamoto_1997, title={A self-consistent method for complete small-signal parameter extraction of InP-based heterojunction bipolar transistors (HBT's)}, volume={45}, url={http://dx.doi.org/10.1109/22.552030}, DOI={10.1109/22.552030}, abstractNote={A complete method for parameter extraction from small-signal measurements of InP-based heterojunction bipolar transistors (HBT's) is presented. Employing analytically derived equations, a numerical solution is sought for the best fit between the model and the measured data. Through parasitics extraction and an optimization process, a realistic model for a self-aligned HBT technology is obtained. The results of the generated s-parameters from the model for a 2/spl times/10 /spl mu/m/sup 2/ emitter area device are presented over a frequency range of 250 MHz-36 GHz with excellent agreement to the measured data.}, number={1}, journal={IEEE Transactions on Microwave Theory and Techniques}, author={Rios, J.M.M. and Lunardi, L.M. and Chandrasekhar, S. and Miyamoto, Y.}, year={1997}, pages={39–45} } @inproceedings{lunardi_1997, title={InP-based monolithically integrated photoreceivers}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0030681951&partnerID=MN8TOARS}, booktitle={Conference Proceedings - International Conference on Indium Phosphide and Related Materials}, author={Lunardi, L.M.}, year={1997}, pages={471–474} } @article{garrett_chandrasekhar_zyskind_sulhoff_dentai_burrus_lunardi_derosier_1997, title={Performance of 8-channel OEIC receiver array in 8 x 2.5 Gb/s WDM transmission experiment}, volume={9}, url={http://dx.doi.org/10.1109/68.553103}, DOI={10.1109/68.553103}, abstractNote={The performance of an 8-channel, 2.5-Gb/s OEIC photoreceiver array in an 8-wavelength long-distance WDM testbed is described. The sensitivity penalties due to crosstalk and transmission are measured, and the source of crosstalk is investigated. Channel sensitivities range from -25.4 to -26.2 dBm after transmission through 720 km of standard fiber, with transmission penalties ranging from 0.3-1.0 dB. When the power in each of seven interfering channels is 5 dB above sensitivity, the maximum cross talk penalty suffered by an individual channel does not exceed 1 dB. These experiments are the first comprehensive characterization of monolithic receiver arrays for crosstalk performance under multichannel operation in a realistic system environment.}, number={2}, journal={IEEE Photonics Technology Letters}, author={Garrett, L.D. and Chandrasekhar, S. and Zyskind, J.L. and Sulhoff, J.W. and Dentai, A.G. and Burrus, C.A. and Lunardi, L.M. and Derosier, R.M.}, year={1997}, month={Feb}, pages={235–237} } @inproceedings{garrett_chandrasekhar_zyskind_sulhoff_dentai_burrus_lunardi_derosier_1997, title={Performance of eight-channel InP p-i-n/HBT receiver array in 8×2.5 Gbit/s wavelength-division multiplexed transmission experiment}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0030714247&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Garrett, L.D. and Chandrasekhar, S. and Zyskind, J.L. and Sulhoff, J.W. and Dentai, A.G. and Burrus, C.A. and Lunardi, L.M. and Derosier, R.M.}, year={1997}, pages={14–15} } @article{garrett_chandrasekhar_zyskind_sulhoff_dentai_burrus_lunardi_derosier_1997, title={Performance of eight-channel OEIC p-i-n/HBT receiver array in 8×2.5 Gb/s WDM transmission system}, volume={15}, url={http://dx.doi.org/10.1109/50.580823}, DOI={10.1109/50.580823}, abstractNote={The performance of an eight-channel, 2.5 Gb/s OEIC photoreceiver array in an eight-wavelength long-distance WDM testbed is described. The sensitivity penalties due to crosstalk and transmission are measured, and the source of crosstalk is investigated. Channel sensitivities range from -25.4 to -26.2 dBm after transmission through 720 km of standard fiber, with transmission penalties ranging from 0.3 dB to 1.0 dB. When the power in each of seven interfering channels is 5 dB above sensitivity, the maximum crosstalk penalty suffered by an individual channel does not exceed 1 dB. These experiments are the first comprehensive characterization of monolithic receiver arrays for crosstalk performance under multichannel operation in a realistic system environment.}, number={5}, journal={Journal of Lightwave Technology}, author={Garrett, L.D. and Chandrasekhar, S. and Zyskind, J.L. and Sulhoff, J.W. and Dentai, A.G. and Burrus, C.A. and Lunardi, L.M. and Derosier, R.M.}, year={1997}, month={May}, pages={827–832} } @article{kim_kim_kim_hwang_miller_das_rios_lunardi_1997, title={[]}, volume={29}, url={http://dx.doi.org/10.1023/a:1018589903010}, DOI={10.1023/a:1018589903010}, number={10}, journal={Optical and Quantum Electronics}, author={Kim, J.B. and Kim, M.J. and Kim, S.J. and Hwang, W.-Y. and Miller, D.L. and Das, M.B. and Rios, J.M.M. and Lunardi, L.M.}, year={1997}, pages={953–959} } @inproceedings{10-gbit/s penalty-free optical transmission over 102.5 km of standard fiber using 1.3-μm electroabsorption modulated laser and raman amplifier_1996, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0029705732&partnerID=MN8TOARS}, booktitle={Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS}, year={1996}, pages={2–3} } @article{samelis_pavlidis_chandrasekhar_lunardi_1996, title={Analysis of the large-signal characteristics of InP/ InGaAs-based optoelectronic preamplifiers}, volume={11}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0030086809&partnerID=MN8TOARS}, DOI={10.1002/(sici)1098-2760(19960220)11:3<163::aid-mop14>3.0.co;2-c}, abstractNote={A model for soft breakdown effects in Inp/InGaAs-based single HBTs is developed. The effects of large-signal excitation on the operational characteristics of optoelectronic preamplifiers, such as the transducer and transimpedance gain of individual transistors, are addressed. These effects depend on optoelectronic integrated-circuit (OEIC) design and are associated with self-bias variations due to input power levels. Cascode designs are relatively immune to these effects, whereas basic coupled amplifiers are more sensitive (9-dB Ω vs. 3-dB Ω transimpedance reduction) for the same input power increase from −35 to −5 dBm. © 1996 John Wiley & Sons, Inc.}, number={3}, journal={Microwave and Optical Technology Letters}, author={Samelis, A. and Pavlidis, D. and Chandrasekhar, S. and Lunardi, L.M.}, year={1996}, pages={163–168} } @inproceedings{lunardi_chandrasekhar_1996, title={Integrated p-i-n/HBT photoreceivers for optical communications}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0030383548&partnerID=MN8TOARS}, booktitle={Technical Digest - International Electron Devices Meeting}, author={Lunardi, L.M. and Chandrasekhar, S.}, year={1996}, pages={645–648} } @article{chandrasekhar_garrett_lunardi_dentai_burrus_burrows_1996, title={Investigation of crosstalk performance of eight-channel p-i-n/HBT OEIC photoreceiver array modules}, volume={8}, url={http://dx.doi.org/10.1109/68.491594}, DOI={10.1109/68.491594}, abstractNote={Detailed measurements of crosstalk under multichannel operation of several eight-channel p-i-n/HBT monolithic array photoreceiver modules are reported. At an operating speed of 2.5 Gb/s, with an average sensitivity of -25 dBm, crosstalk penalties ranging from 0.2 dB to 2.6 dB for a bit-error rate of 10/sup -9/ have been measured for adjacent channels receiving -22 dBm to -12 dBm of optical signal power. This is the first report of the crosstalk performance of a fully packaged OEIC array photoreceiver module.}, number={5}, journal={IEEE Photonics Technology Letters}, author={Chandrasekhar, S. and Garrett, L.D. and Lunardi, L.M. and Dentai, A.G. and Burrus, C.A. and Burrows, E.C.}, year={1996}, month={May}, pages={682–684} } @inproceedings{kim_kim_park_kim_kim_hwang_miller_das_rios_lunardi_1996, title={Large-area InAlAs/InGaAs Schottky barrier enhanced metal semiconductor metal photodiode with low dark current}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0030397433&partnerID=MN8TOARS}, booktitle={Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS}, author={Kim, J.-B. and Kim, M.-J. and Park, J.-W. and Kim, D.-H. and Kim, S.-J. and Hwang, W.-Y. and Miller, D.L. and Das, M.B. and Rios, J.M.M. and Lunardi, L.M.}, year={1996}, pages={330–331} } @article{samelis_pavlidis_chandrasekhar_lunardi_rios_1996, title={Large-signal characteristics of InP-based heterojunction bipolar transistors and optoelectronic cascode transimpedance amplifiers}, volume={43}, url={http://dx.doi.org/10.1109/16.544374}, DOI={10.1109/16.544374}, abstractNote={A large-signal model for InP/InGaAs-based single HBTs incorporating soft-breakdown effects to the LIBRA Gummel-Poon (GP) model is developed and its validity is established from DC to microwave frequencies and over a wide range of input excitation levels. The large-signal characteristics of a cascode InP-based transimpedance optoelectronic preamplifier employing such devices are studied. Gain compression for the preamplifier was found to take place at an input power level of -20 dBm. Input power excitation varying from -65 to -5 dBm results in a degradation of the amplifier transimpedance gain of the order of 3 dBn. Experimental and theoretical characteristics are presented for the InP-based HBTs and transimpedance amplifier. Self-biasing effects are suggested as possible origin of the transimpedance variations with input power.}, number={12}, journal={IEEE Transactions on Electron Devices}, author={Samelis, A. and Pavlidis, D. and Chandrasekhar, S. and Lunardi, L.M. and Rios, J.}, year={1996}, pages={2053–2061} } @article{hamm_chandrasekhar_lunardi_geva_malik_humphrey_ryan_1996, title={Materials and electrical characteristics of carbon-doped Ga0.47In0.53As using carbontetrabromide by MOMBE for HBT device applications}, volume={164}, url={http://dx.doi.org/10.1016/0022-0248(96)00004-8}, DOI={10.1016/0022-0248(96)00004-8}, abstractNote={Metalorganic molecular beam epitaxy (MOMBE) growth of C-doped Ga0.47In0.53As heterostructures and Ga0.47In0.53AsInP heterostructure bipolar transistors (HBT) using carbontetrabromide (CBr4) as the dopant source is reported. Hall, secondary ion mass spectrometry (SIMS), and X-ray data were used to characterize the bulk CGa0.47In0.53As material. The incorporation of C showed a power dependence on the group V beam flux of −0.29 and −0.75 for solid arsenic and AsH3 sources, respectively. This may be related to the change in group V vacancy concentration as the group V beam flux is varied. X-ray measurements of C-doped layers indicated a contraction in the lattice parameter larger than would be calculated using Vegard's law. Doping levels from 2 × 1017 to 7 × 1019cm−3 were measured with mobilities ranging from 105 to 40 cm2/V · s, respectively. SIMS data showed very abrupt profiles with no apparent memory effects. Hydrogen was also measured in the layers and annealing of samples in vacuum showed an increase in doping, of at most 50%, only for samples grown at lower temperatures, about 450°C. For most samples, however, an increase in the mobility was measured after annealing, indicating that the neutral CH complexes most likely contribute to the majority carrier scattering. Large area devices with varying base thickness, WB, and base doping, p, were fabricated. Devices showed good Gummel characteristics with nc = 1.15 and nb = 1.17. The gain variation for different devices was found to be proportional to 1(WBp)2, which is consistent with a diffusive base transport and Auger-dominated recombination in the heavily doped base region. A comparison with Be-doped devices showed the same trend with slightly higher gains. It was also observed that in devices where the C-doped base was grown at temperatures 500°C the gain was shifted to much lower values. Small devices were also fabricated and measured with fT and fmax values of 70 and 50 GHz, respectively.}, number={1-4}, journal={Journal of Crystal Growth}, author={Hamm, R.A. and Chandrasekhar, S. and Lunardi, L. and Geva, M. and Malik, R. and Humphrey, D. and Ryan, R.}, year={1996}, month={Jul}, pages={362–370} } @article{kirtania_das_chandrasekhar_lunardi_qua_hamm_yang_1996, title={Measurement and comparison of 1/f noise and g-r noise in silicon homojunction and III-V heterojunction bipolar transistors}, volume={43}, url={http://dx.doi.org/10.1109/16.491256}, DOI={10.1109/16.491256}, abstractNote={This paper experimentally determines and compares the 1/f noise and the g-r noise, as components of the base noise current spectral density, in Si homojunction and III-V heterojunction bipolar transistors (HBTs) in common-emitter configuration. The noise spectra for each of these devices are obtained as functions of the base bias current (I/sub B/), and the 1/f noise has been found to depend on I/sub B/ as I/sub B//sup /spl gamma//, where /spl gamma//spl sim/1.8 for the silicon BJT's and InP/InGaAs HBT's with high current gains (/spl beta//spl sim/50), and /spl gamma//spl sim/1.1 for the AlGaAs/GaAs HBTs with low current gains (4>}, number={11}, journal={IEEE Photonics Technology Letters}, author={Gutierrez-Aitken, A.L. and Yang, K. and Zhang, X. and Haddad, G.I. and Bhattacharya, P. and Lunardi, L.M.}, year={1995}, month={Nov}, pages={1339–1341} } @inproceedings{lunardi_chandrasekhar_gnauck_burrus_hamm_1995, title={20 Gb/s monolithic p-i-n/HBT photoreceiver module for 1.55 μm applications}, volume={2}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0029453480&partnerID=MN8TOARS}, booktitle={European Conference on Optical Communication, ECOC}, author={Lunardi, L.M. and Chandrasekhar, S. and Gnauck, A.H. and Burrus, C.A. and Hamm, R.A.}, year={1995}, pages={657–660} } @article{lunardi_chandrasekhar_gnauck_burrus_hamm_1995, title={20-Gb/s monolithic p-i-n/HBT photoreceiver module for 1.55-μm applications}, volume={7}, url={http://dx.doi.org/10.1109/68.466590}, DOI={10.1109/68.466590}, abstractNote={A photoreceiver, composed of a p-i-n photodetector monolithically integrated with an InP-InGaAs heterojunction bipolar transistor (HBT)-based transimpedance amplifier, has been fabricated from metal-organic molecular beam epitaxy (MOMBE) material. The fiber-pigtailed module has measured sensitivities of -20.4 dBm and -17.0 dBm for data rates of 10 Gb/s and 20 Gb/s, respectively, at a bit-error-rate of 1/spl times/10/sup -9/. High-speed operation has been achieved with modest (3 /spl mu/m) device dimensions. These results are the best ever reported for an OEIC photoreceiver at these speeds.<>}, number={10}, journal={IEEE Photonics Technology Letters}, author={Lunardi, L.M. and Chandrasekhar, S. and Gnauck, A.H. and Burrus, C.A. and Hamm, R.A.}, year={1995}, month={Oct}, pages={1201–1203} } @article{lunardi_chandrasekhar_gnauck_burrus_sulhoff_zyskind_hamm_1995, title={A 12-Gb/s high-performance, high-sensitivity monolithic p-i-n/HBT photoreceiver module for long-wavelength transmission systems}, volume={7}, url={http://dx.doi.org/10.1109/68.345916}, DOI={10.1109/68.345916}, abstractNote={A very high sensitivity, high speed, fiber-pigtailed photoreceiver module is described. The OEIC photoreceiver, composed of a p-i-n photodetector monolithically integrated with an InP-InGaAs heterojunction bipolar transistor (HBT)-based transimpedance amplifier, has measured sensitivity of -20 dBm and -17.6 dBm for data rates of 10 and 12 Gb/s, respectively, at a bit error rate of 1/spl times/10/sup -9/. These results are the best ever reported for an OEIC photoreceiver at these speeds. In an optical transmission experiment with a low noise erbium-doped fiber amplifier (EDFA) preceding the OEIC photoreceiver, the measured sensitivities were -35.2 and -32 dBm at 10 and 12 Gb/s respectively.<>}, number={2}, journal={IEEE Photonics Technology Letters}, author={Lunardi, L.M. and Chandrasekhar, S. and Gnauck, A.H. and Burrus, C.A. and Sulhoff, J.W. and Zyskind, J.L. and Hamm, R.A.}, year={1995}, month={Feb}, pages={182–184} } @article{hamm_malik_humphrey_ryan_chandrasekhar_lunardi_geva_1995, title={Carbon doping of Ga0.47In0.53As using carbontetrabromide by metalorganic molecular beam epitaxy for InP‐based heterostructure bipolar transistor devices}, volume={67}, url={http://dx.doi.org/10.1063/1.115111}, DOI={10.1063/1.115111}, abstractNote={Metalorganic molecular beam epitaxy of carbon‐doped heterostructures and InP/Ga0.47In0.53As heterostructure bipolar transistors using carbontetrabromide (CBr4) as the dopant source is reported. Secondary ion mass spectrometry show H incorporation associated with the carbon doping. Hall data for as‐grown and postgrowth annealed samples showed a clear increase in doping only for samples grown at the lowest temperature, 450 °C, and higher doping levels. An increase in the mobility, however, was measured for nearly all samples after annealing, indicating that the neutral C–H complexes most likely contribute to majority carrier scattering. The gain variation for various devices with base thickness, WB, and base doping, p, was found to be nearly proportional to 1/(WB×p)2 consistent with diffusive base transport and Auger dominated recombination in the heavily doped base region. It was also observed that in devices where the C‐doped base was grown at temperatures ≳500 °C, the gain was shifted to much lower value...}, journal={Applied Physics Letters}, author={Hamm, R.A. and Malik, R. and Humphrey, D. and Ryan, R. and Chandrasekhar, S. and Lunardi, L. and Geva, M.}, year={1995}, month={Oct}, pages={2226} } @article{hamm_chandrasekhar_lunardi_geva_1995, title={Characteristics of carbon doped InGaAs using carbontetrabromide by metalorganic molecular beam epitaxy}, volume={148}, url={http://dx.doi.org/10.1016/0022-0248(94)00862-0}, DOI={10.1016/0022-0248(94)00862-0}, abstractNote={Carbon-doped In0.53Ga0.47As structures have been grown on InP by metalorganic molecular beam epitaxy using carbontetrabromide as the dopant source. Hall, secondary ion mass spectrometry (SIMS) and X-ray measurements were done to characterize the material. Doping levels from 2 × 1017 to 7 × 1019 cm−3 were measured with mobilities ranging from 100 to 45 cm2/V · s. SIMS data show very abrupt doping profiles with no apparent memory effects. Hydrogen was measured in the C doped regions, however, no passivation effects were observed and Hall and SIMS data agreed within experimental error. Post-growth anneals of the highest doped samples showed no change in carrier concentration. The incorporation of C showed a strong dependence on the group V beam flux (concentration ∼ flow−34). We believe that this is related to the change in group V vacancy concentration as the group V beam flux is varied. A smaller dependence of C incorporation was also observed with the growth temperature.}, number={1-2}, journal={Journal of Crystal Growth}, author={Hamm, R.A. and Chandrasekhar, S. and Lunardi, L. and Geva, M.}, year={1995}, month={Feb}, pages={1–7} } @inproceedings{chandrasekhar_lunardi_1995, title={High-performance p-i-n/HBT monolithic photoreceivers for lightwave communications}, volume={2613}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0029483865&partnerID=MN8TOARS}, booktitle={Proceedings of SPIE - The International Society for Optical Engineering}, author={Chandrasekhar, S. and Lunardi, Leda M.}, year={1995}, pages={91–97} } @inproceedings{samelis_pavlidis_sejalon_chandrasekhar_lunardi_1995, title={Large-signal characteristics of InP-based heterojunction bipolar transistors and their use in optoelectronic preamplifier design}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0029217866&partnerID=MN8TOARS}, booktitle={Conference Proceedings - International Conference on Indium Phosphide and Related Materials}, author={Samelis, A. and Pavlidis, D. and Sejalon, F. and Chandrasekhar, S. and Lunardi, L.M.}, year={1995}, pages={648–651} } @article{chandrasekhar_zirngibl_dentai_joyner_storz_burrus_lunardi_1995, title={Monolithic eight-wavelength demultiplexed receiver for dense WDM applications}, volume={7}, url={http://dx.doi.org/10.1109/68.473492}, DOI={10.1109/68.473492}, abstractNote={A single chip incorporating a waveguide grating router and eight p-i-n photodetectors followed by eight preamplifiers constructed from heterojunction bipolar transistors, has been realized. The chip can demultiplex eight wavelengths spaced 100 GHz (0.81 nm) apart with nearest neighbor crosstalk better than -15 dB. The external quantum efficiency for each of the eight wavelength demultiplexed photodetectors was 5-8% (a responsivity of 0.06-0.10 A/W) and each optical front end operated up to 2.5 Gb/s. This is the first demonstration of monolithic integration of electronic circuits with a wavelength demultiplexer.<>}, number={11}, journal={IEEE Photonics Technology Letters}, author={Chandrasekhar, S. and Zirngibl, M. and Dentai, A.G. and Joyner, C.H. and Storz, F. and Burrus, C.A. and Lunardi, L.M.}, year={1995}, month={Nov}, pages={1342–1344} } @inproceedings{gutierrez-aitken_yang_zhang_haddad_bhattacharya_lunardi_1995, title={Wide bandwidth InAlAs/InGaAs monolithic PIN-HBT photoreceiver}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0029507792&partnerID=MN8TOARS}, booktitle={LEOS Summer Topical Meeting}, author={Gutierrez-Aitken, A.L. and Yang, K. and Zhang, X. and Haddad, G.I. and Bhattacharya, P. and Lunardi, L.M.}, year={1995} } @inproceedings{lunardi_chandrasekhar_gnauck_burrus_hamm_sulhoff_zyskind_1994, title={12 Gb/s high performance, high sensitivity monolithic p-i-n/HBT photoreceiver module for long wavelength transmission systems}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-38449117570&partnerID=MN8TOARS}, booktitle={European Conference on Optical Communication, ECOC}, author={Lunardi, L.M. and Chandrasekhar, S. and Gnauck, A.H. and Burrus, C.A. and Hamm, R.A. and Sulhoff, J.W. and Zyskind, J.L.}, year={1994}, pages={121–124} } @inproceedings{kirtania_das_chandrasekhar_lunardi_hamm_yang_1994, title={Comparison of low-frequency noise characteristics of silicon homojunction and III-V heterojunction bipolar transistors}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0028202020&partnerID=MN8TOARS}, booktitle={Conference Proceedings - International Conference on Indium Phosphide and Related Materials}, author={Kirtania, Ashish K. and Das, Mukunda B. and Chandrasekhar, S. and Lunardi, L.M. and Hamm, R.A. and Yang, L.W.}, year={1994}, pages={535–538} } @article{chandrasekhar_lunardi_qua_1994, title={Eight-Channel p-i-n/HBT Monolithic Receiver Array at 2.5 Gb/s Per Channel for WDM Applications}, volume={6}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0028524224&partnerID=MN8TOARS}, DOI={10.1109/68.329643}, abstractNote={We report a monolithic chip incorporating an eight channel p-i-n/HBT photoreceiver array designed for multichannel WDM applications. The p-i-n photodetectors are edge illuminated and centered at a 250 /spl mu/m pitch for mating with either ribbon fiber connectors or waveguide demultiplexers. Each channel operates at 2.5 Gb/s with an electrical crosstalk of -20 dB between adjacent channels. The average sensitivity of each receiver in the array was measured to be (-20/spl plusmn/1) dBm for a bit error rate of 10/sup -9/ at a wavelength of 1.5 /spl mu/m.<>}, number={10}, journal={IEEE Photonics Technology Letters}, author={Chandrasekhar, S. and Lunardi, L.M. and Qua, G.J.}, year={1994}, pages={1216–1218} } @inproceedings{chandrasekhar_lunardi_hamm_qua_1994, title={Eight-channel p-i-n/HBT monolithic receiver array at 2.5 Gb/s per channel for WDM applications}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0028202387&partnerID=MN8TOARS}, booktitle={Conference Proceedings - International Conference on Indium Phosphide and Related Materials}, author={Chandrasekhar, S. and Lunardi, L.M. and Hamm, R.A. and Qua, G.J.}, year={1994}, pages={243–246} } @inproceedings{lunardi_chandrasekhar_swartz_hamm_qua_1994, title={High-speed burst-mode OEIC photoreceiver using InP/InGaAs heterojunction bipolar transistors}, volume={4}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0028135955&partnerID=MN8TOARS}, booktitle={Conference on Optical Fiber Communication, Technical Digest Series}, author={Lunardi, L.M. and Chandrasekhar, S. and Swartz, R.G. and Hamm, R.A. and Qua, G.J.}, year={1994}, pages={30–31} } @inproceedings{chandrasekhar_lunardi_liou_1993, title={High speed and high performance long wavelength OEICs using heterojunction bipolar transistors}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85064661128&partnerID=MN8TOARS}, DOI={10.1109/ASIC.1993.410766}, abstractNote={High-speed heterojunction bipolar transistors (HBTs) in the InP/InGaAs material system have been monolithically integrated with p-i-n photodetecters as receivers and with quantum well lasers as transmitters for potential applications in long wavelength lightwave communications. Speeds well beyond 5 Gb/s have been achieved with excellent performance.<>}, booktitle={Proceedings - 6th Annual IEEE International ASIC Conference and Exhibit, ASIC 1993}, author={Chandrasekhar, S. and Lunardi, L.M. and Liou, K.-Y.}, year={1993}, pages={490–493} } @article{lunardi_chandrasekhar_1993, title={High-Speed, High-Current-Gain P-n-p InP/InGaAs Heterojunction Bipolar Transistors}, volume={14}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0027230627&partnerID=MN8TOARS}, DOI={10.1109/55.215087}, abstractNote={p-n-p InP/InGaAs heterojunction bipolar transistors (HBTs) are reported for the first time. The transistors, grown by metal organic molecular beam epitaxy (MOMBE), exhibited maximum DC current gain values up to 420 for a base doping level of 4*10/sup 18/ cm/sup -3/. Small-signal measurements on self-aligned transistors with 3- mu m*8- mu m emitter area indicated the unity gain cutoff frequency value of 10.5 GHz and the inferred maximum frequency of oscillation of 25 GHz. The results clearly demonstrate the feasibility of complementary integrated circuits in the InP material system.<>}, number={1}, journal={IEEE Electron Device Letters}, author={Lunardi, L.M. and Chandrasekhar, S.}, year={1993}, pages={19–21} } @article{chandrasekhar_lunardi_gnauck_qua_hamm_1993, title={High-speed monolithic p-i-n/HBT and HPT/HBT photoreceivers implemented with simple phototransistor structure}, volume={5}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0027699126&partnerID=MN8TOARS}, DOI={10.1109/68.250055}, abstractNote={Monolithic photoreceivers, using the base-collector junction of an InP/InGaAs phototransistor structure for a p-i-n photodetector, have been fabricated for the first time. Bandwidths as high as 3 GHz and bit rates as high as 5 Gb/s, with sensitivities of -22.5 dBm and -21.5 dBm for light focused on the p-i-n or on the first stage transistor of the preamplifier, respectively, have been achieved. These results represent the highest operating speed demonstrated for any phototransistor-based receiver.<>}, number={11}, journal={IEEE Photonics Technology Letters}, author={Chandrasekhar, S. and Lunardi, L.M. and Gnauck, A.H. and Qua, G.J. and Hamm, R.A.}, year={1993}, pages={1316–1318} } @article{chandrasekhar_lunardi_gnauck_ritter_hamm_panish_qua_1992, title={A 10 Gbit/s OEIC photoreceiver using InP/InGaAs heterojunction bipolar transistors}, volume={28}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0026820205&partnerID=MN8TOARS}, DOI={10.1049/el:19920294}, abstractNote={Metal organic molecular beam epitaxy (MOMBE) was successfully used for the first time to realise a high speed monolithic photoreceiver. Incorporating an InGaAs pin photodetector followed by a transimpedance preamplifier circuit implemented with InP/InGaAs heterojunction bipolar transistors (HBTs), the OEIC photoreceiver had a bandwidth of 6 GHz and a midband transimpedance of 350 ω. In a system experiment performed at 10 Gbit/s, the receiver exhibited a sensitivity of –15.5 dBm for a bit error rate of 10-9 at a wavelength of 1.53 μm. This is the first demonstration of operation of a long wavelength OEIC photoreceiver at this speed.}, number={5}, journal={Electronics Letters}, author={Chandrasekhar, S. and Lunardi, L.M. and Gnauck, A.H. and Ritter, D. and Hamm, R.A. and Panish, M.B. and Qua, G.J.}, year={1992}, pages={466–468} } @article{lunardi_chandrasekhar_hamm_hamm_1992, title={IVA-8 High-Speed InP/InGaAs p-n-p Heterojunction Bipolar Transistors}, volume={39}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0026955608&partnerID=MN8TOARS}, DOI={10.1109/16.163522}, abstractNote={Summary form only given. The authors report InP/InGaAs p-n-p HBTs (heterojunction bipolar transistors), grown by metal-organic molecular beam epitaxy (MOMBE) and demonstrate large current gain and high speed. A transistor with an emitter dimension of 3*8 gmm/sup 2/ had a common emitter current gain of 30 at a collector current density of 2*10/sup 4/ A/cm/sup 2/. Microwave on-wafer measurements were done to characterize the small-signal performance of the transistors. The unity gain cutoff frequency f/sub T/ was 12 GHz and the inferred maximum oscillation frequency f/sub max/ was 20 GHz, at a collector current of 2.5 mA and a collector-to-emitter voltage of 5.0 V. >}, number={11}, journal={IEEE Transactions on Electron Devices}, author={Lunardi, L.M. and Chandrasekhar, S. and Hamm, R.A. and Hamm, R.A.}, year={1992}, pages={2659} } @article{lunardi_sen_capasso_smith_sivco_cho_1992, title={Microwave multiple-state resonant tunneling bipolar transistors}, volume={v}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-34250837017&partnerID=MN8TOARS}, number={n}, journal={Electron device letters}, author={Lunardi, L.M. and Sen, S. and Capasso, F. and Smith, P.R. and Sivco, D.L. and Cho, A.Y.}, year={1992}, pages={219–221} } @inproceedings{lunardi_chandrasekhar_1992, title={Optoelectronic applications of heterojunction bipolar transistor technology: promises and problems}, volume={1680}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0026961894&partnerID=MN8TOARS}, booktitle={Proceedings of SPIE - The International Society for Optical Engineering}, author={Lunardi, Leda M. and Chandrasekhar, S.}, year={1992}, pages={27–32} } @inproceedings{malik_lunardi_levine_bethea_beltram_ralph_hopkins_capasso_1990, title={Band gap engineering of III-V semiconductors by MBE using electron beam evaporation of group III metals}, volume={1285}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0025538484&partnerID=MN8TOARS}, DOI={10.1117/12.20809}, abstractNote={Graded band gap ITT-V semiconductor structures have been grown by molecular beam epitaxy using electron beam evaporation of Group III metals. The deposition rates of the Group III metals are measured and controlled in real-time using Inficon Sentinel III rate monitors. The rapid response of the electron beam evaporation sources allows precise alloy grading over distances as short as 1 nm. A variety of novel 111-V device structures have been realized by this technique.}, booktitle={Proceedings of SPIE - The International Society for Optical Engineering}, author={Malik, R.J. and Lunardi, L.M. and Levine, B.F. and Bethea, C.G. and Beltram, F. and Ralph, S.E. and Hopkins, L.C. and Capasso, F.}, year={1990}, pages={76–84} } @article{hobson_ren_abernathy_pearton_fullowan_lothian_jordan_lunardi_1990, title={Carbon-Doped Base GaAs-AlGaAs HBT's Grown by MOMBE and MOCVD Regrowth}, volume={11}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0025446457&partnerID=MN8TOARS}, DOI={10.1109/55.55267}, abstractNote={High-quality GaAs-AlGaAs heterojunction bipolar transistors (HBTs) in which the carbon-doped base layers (p=10/sup 10/-10/sup 20/ cm/sup -3/, 400-800 AA thick) and Sn-doped collector and subcollector layers are grown by metalorganic molecular-beam epitaxy (MOMBE) and a subsequent regrowth using metalorganic chemical vapor deposition (MOCVD) is used to provide the n/sup +/ AlGaAs emitter and GaAs/InGaAs contact layers are discussed. A current gain of 20 was obtained for a base doping of 10/sup 19/ cm/sup -3/ (800 AA thick) in a 90- mu m-diameter device, with ideality factors of 1.0 and 1.4 for the base-collector and emitter-base junctions, respectively, demonstrating the excellent regrowth-interface quality. For a base doping of 10/sup 20/ cm/sup -3/ (400 AA thick), the current gain decreased to 8.<>}, number={6}, journal={IEEE Electron Device Letters}, author={Hobson, W.S. and Ren, F. and Abernathy, C.R. and Pearton, S.J. and Fullowan, T.R. and Lothian, J. and Jordan, A.S. and Lunardi, L.M.}, year={1990}, pages={241–243} } @inproceedings{lunardi_malik_ryan_smith_shunk_feuer_fullowan_1990, title={Characteristics of AlGaAs/GaAs thin emitter heterojunction bipolar transistors}, volume={1288}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0025670991&partnerID=MN8TOARS}, DOI={10.1117/12.20906}, abstractNote={Ultra thin (100-200 A) AlGaAs emitter layers have been incorporated in AlGaAs/GaAs Heterojunction Bipolar Transistors (HBTs). Fabricated using a self-aligned process technology, this novel structure has yielded transistors with submicron emitter widths. The AlGaAs emitter layer serves to passivate the base surface resulting in constant current gain values of 25 for all geometries independent of emitter area. The maximum cutoff frequency obtained was 35 GHz with a corresponding 38 GHz for the maximum frequency of oscillation for a 1.3?m x 9 ?m emitter area device.}, booktitle={Proceedings of SPIE - The International Society for Optical Engineering}, author={Lunardi, L.M. and Malik, R.J. and Ryan, R.W. and Smith, P.R. and Shunk, S.C. and Feuer, M.D. and Fullowan, T.R.}, year={1990}, pages={44–56} } @article{lunardi_archer_swartz_kuo_kopf_malik_smith_1990, title={High Speed Linear Array Circuit with AIGaAs/Gaas Heterojunction Bipolar Transistors (HBTs)}, volume={26}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0025464809&partnerID=MN8TOARS}, DOI={10.1049/el:19900748}, abstractNote={Direct comparison of the performance of a digital divide-by-two implemented in a linear array configuration with an optimised layout version has been made, using AlGaAs/GaAs HBTs in 3.5 μm emitter width technology with a cutoff frequency of 40 GHz. The customised version operated up to 7.5 GHz input frequency. The linear array circuit operated up to 7.05 GHz.}, number={15}, journal={Electronics Letters}, author={Lunardi, L.M. and Archer, V.D. and Swartz, R.G. and Kuo, J.M. and Kopf, R.F. and Malik, R.J. and Smith, P.R.}, year={1990}, pages={1157–1159} } @article{swartz_lunardi_malik_archer_feuer_walker_fullowan_1989, title={AIGaAs/GaAs Heterojunction Bipolar Transistor Decision Circuit}, volume={25}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0024305430&partnerID=MN8TOARS}, DOI={10.1049/el:19890087}, abstractNote={An AlGaAs/GaAs heterojunction bipolar transistor (HBT) decision circuit has been designed and characterised for optical communications, using 3.5 μm emitter width transistors with cutoff frequency of 27 GHz. The maximum bit rate for a BER of 10−9 was 4.2 Gbit/s. At 2.0 Gbit/s, the dock phase margin was 240°.}, number={2}, journal={Electronics Letters}, author={Swartz, R.G. and Lunardi, L.M. and Malik, R.J. and Archer, V.D. and Feuer, M.D. and Walker, J.F. and Fullowan, T.R.}, year={1989}, pages={118–119} } @article{schubert_tu_kopf_kuo_lunardi_1989, title={Diffusion and drift of Si dopants in δ-doped n-type Al xGa1-xAs}, volume={54}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-36549100692&partnerID=MN8TOARS}, DOI={10.1063/1.101059}, abstractNote={The study of diffusion and drift of Si in AlxGa1−xAs by means of capacitance‐voltage measurements reveals that low substrate temperatures during growth by molecular beam epitaxy are required to achieve δ‐function‐like doping profiles. The diffusion coefficient of Si in Al0.3Ga0.7As is determined. We further show theoretically that the random Poisson distribution (usually assumed for dopant distributions in semiconductors) should be modified at high dopant concentrations due to repulsive interactions of impurities.}, number={25}, journal={Applied Physics Letters}, author={Schubert, E.F. and Tu, C.W. and Kopf, R.F. and Kuo, J.M. and Lunardi, L.M.}, year={1989}, pages={2592–2594} } @article{pearton_abernathy_panish_hamm_lunardi_1989, title={Implant-induced high-resistivity regions in InP and InGaAs}, volume={66}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-21544456296&partnerID=MN8TOARS}, DOI={10.1063/1.343533}, abstractNote={We have investigated the effects of ion bombardment on the electrical properties of intentionally doped InP and InGaAs grown by metalorganic molecular‐beam epitaxy. The sheet resistivity and mobility of n+InP (Sn) and n+InGaAs (Sn) or p+InGaAs (Be) epilayers grown on semi‐insulating InP substrates were measured as a function of ion species (O, B, H, or Fe), ion dose (1012–1015 cm−2), and post‐implant annealing temperature (100–600 °C). In n+InP, the resistivity after bombardment goes through a maximum with annealing temperature, reaching a value of ∼106 Ω/⧠ for 0.5‐μm‐thick films after implantation with H or O and annealing at 200–300 °C. The as‐grown resistivity is restored by annealing above 500 °C. Ion doses below 1012 cm−2 actually lead to a decrease in resistivity through the creation of shallow donor levels. By contrast, the implantation of Fe above a critical dose where the Fe density exceeds the dopant concentration leads to the formation of thermally stable, high‐resistivity (>106 Ω/⧠) material. ...}, number={2}, journal={Journal of Applied Physics}, author={Pearton, S.J. and Abernathy, C.R. and Panish, M.B. and Hamm, R.A. and Lunardi, L.M.}, year={1989}, pages={656–662} } @article{lunardi_capasso_smith_sivco_cho_1989, title={Microwave Multiple-State Resonant-Tunneling Bipolar Transistors}, volume={10}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84915300890&partnerID=MN8TOARS}, DOI={10.1109/55.31726}, abstractNote={Fabrication and microwave performance of a multiple-state resonant-tunneling bipolar transistor (RTBT) are presented. This transistor exhibits a maximum DC current gain of 60 at room temperature and a cutoff frequency of 24 GHz. Frequency multiplication by a factor of five has been demonstrated with a single transistor.<>}, number={5}, journal={IEEE Electron Device Letters}, author={Lunardi, L.M. and Capasso, F. and Smith, P.R. and Sivco, D.L. and Cho, A.Y.}, year={1989}, pages={219–221} } @article{capasso_sen_beltram_lunardi_vengurlekar_smith_shah_malik_cho_1989, title={Quantum Functional Devices: Resonant-Tunneling Transistors, Circuits with Reduced Complexity, and Multiple-Valued Logic}, volume={36}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0024750508&partnerID=MN8TOARS}, DOI={10.1109/16.40888}, abstractNote={Recent advances in the area of quantum functional devices are discussed. After a discussion of the functional device concept, resonant-tunneling bipolar transistors (RTBTs) with a double barrier in the base region are described. Design considerations for RTBTs with ballistic injection and the first observation of minority-electron ballistic RT are presented. RTBTs using thermionic injection and exhibiting a high peak-to-valley ratio at room temperature in the transfer characteristics are also described. Multiple-state RTBTs and their DC and microwave performance are then discussed. Circuit applications of RTBTs also are discussed. It is shown that RTBTs allow the implementation of many analog and digital circuit functions with a greatly reduced number of transistors and show considerable promise for multiple-valued logic. Experimental results on frequency multipliers and parity bit generators are presented. Analog-to-digital converters are memory circuits are also discussed. Two novel superlattice-base transistors are reported. Negative transconductance is achieved by suppression of injection into minibands. Gated quantum-well RT transistors are also discussed. >}, number={10}, journal={IEEE Transactions on Electron Devices}, author={Capasso, F. and Sen, S. and Beltram, F. and Lunardi, L.M. and Vengurlekar, A.S. and Smith, P.R. and Shah, N.J. and Malik, R.J. and Cho, A.Y.}, year={1989}, pages={2065–2082} } @article{malik_lunardi_ryan_shunk_feuer_1989, title={Submicron scaling of AlGaAs/GaAs self-aligned thin emitter heterojunction bipolar transistors (SATE-HBT) with current gain independent of emitter area}, volume={25}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0024716469&partnerID=MN8TOARS}, DOI={10.1049/el:19890788}, abstractNote={A new, self-aligned process technology for AlGaAs/GaAs heterojunction bipolar transistors (HBT) has been developed, which is based upon ultrathin (100–200 A) AlGaAs emitter layers. The thin AlGaAs emitter is used as a selective etch stop layer for contacting the p+ base layer and acts as an integral surface passivation layer which eliminates recombination currents in the extrinsic base region. This novel technology yields transistors with emitter dimensions as small as 0.3 × 4.0 µm2 and current gain values independent of emitter area.}, number={17}, journal={Electronics Letters}, author={Malik, R.J. and Lunardi, L.M. and Ryan, R.W. and Shunk, S.C. and Feuer, M.D.}, year={1989}, pages={1175–1177} } @article{malik_lunardi_walker_ryan_1988, title={A Planar-Doped 2D-Hole Gas Base AlGaAs/GaAs Heterojunction Bipolar Transistor Grown by Molecular Beam Epitaxy}, volume={9}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0023833453&partnerID=MN8TOARS}, DOI={10.1109/55.20396}, abstractNote={A novel type of AlGaAs/GaAs heterojunction bipolar transistor (HBT) which uses a two-dimensional (2-D) hole gas base formed by planar doping using molecular-beam epitaxy (MBE) has been demonstrated. The base consists of a submonolayer of Be atoms of sheet concentration 0.5-5*10/sup 13/ cm/sup -2/ which is deposited during growth interruption by MBE. The transistor structure exhibits DC current gains up to 700. The effective base transit time is negligible in these transistors and it is postulated that very high-speed nonequilibrium transport may occur in the collector region.<>}, number={1}, journal={IEEE Electron Device Letters}, author={Malik, R.J. and Lunardi, L.M. and Walker, J.F. and Ryan, R.W.}, year={1988}, pages={7–9} } @inproceedings{enquist_lunardi_welch_wicks_shealy_eastman_calawa_1985, title={OPTIMIZATION OF THE INJECTION EFFICIENCY ( gamma ) OF THE HBT BY STUDYING ELECTROLUMINESCENCE (EL) OF MBE HETEROJUNCTION DIODES.}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0022247171&partnerID=MN8TOARS}, number={74}, booktitle={Institute of Physics Conference Series}, author={Enquist, P. and Lunardi, L.M. and Welch, D.F. and Wicks, G.W. and Shealy, J.R. and Eastman, L.F. and Calawa, A.R.}, year={1985}, pages={599–604} } @article{ankri_schaff_barnard_lunardi_eastman_1983, title={High-speed GaAs heterojunction bipolar phototransistor grown by molecular beam epitaxy}, volume={19}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0020737470&partnerID=MN8TOARS}, DOI={10.1049/el:19830195}, abstractNote={A novel heterojunction phototransistor (HPT) structure is proposed using two base regions such that the emitter-base depletion region is located in the wide-gap material. Very small area HPTs have been fabricated on semi-insulating substrates. Maximum current gain is s = 300. The response time, with rise time as short as 250 ps and FWHM = 320 ps, has been obtained using a picosecond pulse dye laser.}, number={8}, journal={Electronics Letters}, author={Ankri, D. and Schaff, W.J. and Barnard, J. and Lunardi, L. and Eastman, L.F.}, year={1983}, pages={278–280} } @inproceedings{inp-based monolithically integrated photoreceivers, url={http://dx.doi.org/10.1109/iciprm.1997.600196}, DOI={10.1109/iciprm.1997.600196}, abstractNote={Photoreceivers, composed by a InGaAs photodetector monolithically integrated with either field-effect or bipolar transistor-based amplifiers, have achieved high-speed and high-sensitivities up to 20 Gb/s in single channel or aggregated throughput in multichannel configurations. A review of high performance InP-based technologies targeted to fiber optic communication applications is presented.}, booktitle={Conference Proceedings. 1997 International Conference on Indium Phosphide and Related Materials} } @inproceedings{integrated p-i-n/hbt photoreceivers for optical communications, url={http://dx.doi.org/10.1109/iedm.1996.554064}, DOI={10.1109/iedm.1996.554064}, abstractNote={We will review the present status of our optoelectronic integrated circuits (OEICs) for lightwave communications applications. In a single channel, a photoreceiver module, composed of a p-i-n photodetector monolithically integrated with an InP/InGaAs heterojunction bipolar transistor (HBT)-based transimpedance amplifier has measured sensitivity of -17.0 dBm for 20 Gb/s operation, at a bit-error-rate of 10/sup -9/. Eight-channel array modules performed at 2.5 Gb/s with an average sensitivity of -25 dBm and crosstalk penalties ranging from 0.2 to 2.6 dB, for a bit-error-rate of 10/sup -9/.}, booktitle={International Electron Devices Meeting. Technical Digest} } @inproceedings{large-signal characteristics of inp-based heterojunction bipolar transistors and their use in optoelectronic preamplifier design, url={http://dx.doi.org/10.1109/iciprm.1995.522227}, DOI={10.1109/iciprm.1995.522227}, abstractNote={A large-signal model suitable for InP/InGaAs HBTs was developed. Breakdown effects have been incorporated into the Gummel-Poon formulation. The new model was validated by comparisons with on-wafer power measurements. The characteristics of two transimpedance amplifiers of different design were studied using the large-signal models developed for InP/InGaAs HBTs. The analysis showed that circuit characteristics can be modified under large-signal operation. Transimpedance degradation and pronounced self-bias can, for example, take place and these depend on the type of OEIC. Large-signal modeling should therefore be considered for accurate OEIC design.}, booktitle={Seventh International Conference on Indium Phosphide and Related Materials} }