@article{pandya_maynor_gratton_vellenga_yu_osburn_desimone_2006, title={Fabrication of organic nano-particles by PRINT : Master generation using lithographic and RIE techniques}, volume={6151}, ISBN={["0-8194-6194-6"]}, ISSN={["1996-756X"]}, DOI={10.1117/12.656510}, abstractNote={By using PRINT (Particle Replication In Non-wetting Templates), a general soft technique for replication of diverse shapes at the sub-micron level, we have been able to produce organic nano-particles. Lithographic patterning (using 193nm exposure tool) was employed to generate 160nm posts on a 6" Si wafer; the material of the posts being the organic polymer based commercial photoresist. RIE was then performed on the patterned substrate to transfer the geometry to the Si; various aspect ratios of the Si nano-posts were obtained upon etch time variation. PRINT was used to make a mold of the nano-features on the Si wafer and subsequently fabricate cross-linked organic nano-particles by using PEG-diacrylate (PolyEthylene Glycol diacrylate). Such organic nano-matrices would be potentially useful as therapeutic agent carriers, imaging chemical encapsulants and localized drug delivery vehicles.}, journal={EMERGING LITHOGRAPHIC TECHNOLOGIES X, PTS 1 AND 2}, author={Pandya, Ashish A. and Maynor, Benjamin W. and Gratton, Stephanie E. A. and Vellenga, David G. and Yu, D. Ginger and Osburn, Carlton M. and DeSimone, Joseph M.}, year={2006}, pages={U1396–U1396} }
 @article{yu_chen_holmes_hu_denbaars_1997, title={Comparing ion damage in GaAs and InP}, volume={35}, ISSN={["0167-9317"]}, DOI={10.1016/s0167-9317(96)00163-3}, abstractNote={In this paper, we study argon ion damage in both GaAs and InP. Low temperature photoluminescence measurements of GaAs and InP multiple quantum well (MQW) heterostructures are compared before and after an argon ion bombardment of 500 eV. Computer simulations of the channeling depth and atomic displacement in both materials are also calculated using SCattering of Heavy, Low Energy Ions into CHannels (SCHLEICH). We demonstrate that the range of ion damage in the InP MQW structure appears to be greater than in the GaAs structure and the results from the computer simulations confirm and support these experimental findings.}, number={1-4}, journal={MICROELECTRONIC ENGINEERING}, author={Yu, DG and Chen, CH and Holmes, AL and Hu, EL and DenBaars, SP}, year={1997}, month={Feb}, pages={95–98} }
 @article{yu_chen_holmes_denbaars_hu_1997, title={Role of defect diffusion in the InP damage profile}, volume={15}, ISSN={["1071-1023"]}, DOI={10.1116/1.589706}, abstractNote={Channeling of incident ions and radiation-enhanced diffusion of the ion-created defects have been shown to be major components of the ion damage profile. Our earlier results showed a deeper damage profile in InP, compared to GaAs, when subjected to the same ion bombardment conditions. Computer simulations demonstrated that this can partially be attributed to the greater ion channeling range in InP. In this article the role of defect diffusion in InP, through experiments coupled with simulations, is delineated. The multiple quantum well (MQW) probe technique is used to determine the amount of damage by measuring the change in low temperature photoluminescence of quantum wells before and after argon ion bombardment. A blocking superlattice is added to the MQW heterostructure and is proven effective in preventing damage from propagating into the material below it. By correlating the experimental results with computer modeling, an estimate of the defect diffusion constant is obtained and it is found to be in the range of 4×10−15–1×10−14 cm2/s. These high values for diffusion are justified with experimental results that illustrate the presence of radiation-enhanced diffusion mechanisms during ion bombardment.}, number={6}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B}, author={Yu, DG and Chen, CH and Holmes, AL and DenBaars, SP and Hu, EL}, year={1997}, pages={2672–2675} }
 @article{investigation of improved regrowth material on inp surfaces etched with methane/hydrogen/argon_1996, volume={B13}, number={3674}, journal={Journal of Vacuum Science & Technology}, year={1996} }
 @inproceedings{ion damage propagation in dry-etched inp-based structures_1996, DOI={10.1109/iciprm.1996.491946}, abstractNote={The high spatial resolution, controlled etch profiles and uniformity of etching that is achievable with ion-assisted etch processes appear to be counterbalanced with ion-induced defects introduced into the material. We describe assessments of such damage introduced into InP, and propagated into material structures regrown onto those InP substrates. Particular etch chemistries, effective for patterning InP, may have capabilities of mitigating ion-generated defects.}, booktitle={Proceedings of the Eighth International Conference on Indium Phosphide and Related Materials}, year={1996}, pages={107} }
 @article{chen_yu_hu_petroff_1996, title={Photoluminescence studies on radiation enhanced diffusion of dry-etch damage in GaAs and InP materials}, volume={B13}, journal={Journal of Vacuum Science & Technology}, author={Chen, C.-H and Yu, D.G. and Hu, E.L. and Petroff, P.M.}, year={1996}, pages={3674} }
 @article{yu_keller_holmes_hu_denbaars_1995, title={Analysis of InP etched surfaces using metalorganic chemical vapor deposition regrown quantum well structures}, volume={13}, ISSN={["1071-1023"]}, DOI={10.1116/1.588078}, abstractNote={We have studied a wide variety of wet and dry etching methods for InP substrates and subsequent surface treatments in preparation for regrowth. To evaluate these processes, a multiple quantum well heterostructure consisting of InGaAs quantum wells of varying widths was regrown on these etched surfaces by metalorganic chemical vapor deposition. This heterostructure was chosen so that we could use low temperature photoluminescence to determine etch damage propagation from the surface. We have found that the photoluminescence intensity of regrown quantum wells close to CH4/H2/Ar reactive-ion-etched surfaces is greater than for quantum wells grown the same distance from wet etched surfaces. This technique provides isolation of the characteristics of the etch and clean-up procedure.}, number={6}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B}, author={Yu, DG and Keller, BP and Holmes, AL and Hu, EL and DenBaars, SP}, year={1995}, pages={2381–2385} }
 @article{yu_hu_hasnain_1994, title={RADICAL BEAM ION-BEAM ETCHING OF INALAS/INP USING CL-2}, volume={12}, ISSN={["0734-211X"]}, DOI={10.1116/1.587516}, abstractNote={A Cl2 radical beam ion-beam etching (RBIBE) system was used to etch InP-based materials. In InAlAs/InAlGaAs heterostructures, vertical sidewalls, smooth surfaces, and no delineation of the epilayers resulted from etching at elevated temperatures (≳150 °C) and low ion-beam energies (≤300 eV). Rapid etch rates (≳1 μm/min) were also achieved under these conditions. This work demonstrates that reliable anisotropic and angled etching of InP-based III–V compound semiconductors is possible with the RBIBE system.}, number={6}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B}, author={YU, DG and HU, EL and HASNAIN, G}, year={1994}, pages={3378–3381} }
 @inproceedings{schramm_yu_pekarik_hu_merz_1992, title={Sel-selective formation of organic masks for Methane/Hydrogen reactive ion etching of InP}, DOI={10.1109/iciprm.1992.235680}, abstractNote={It is demonstrated that the polymer byproduct of methane/hydrogen RIE (reactive ion etching) can be used advantageously in forming thin, yet durable etch masks. The thin masking layers are consistent with high-resolution pattern transfer, and are made possible by the etch chemistry itself. A 1000 AA mask can be used to delineate features microns deep in InP. They are particularly useful in in situ processes, such as the metal protection process, where the films are not subjected to the atmosphere until the etch is complete. Although the surface cleaning was sufficient to obtain a patterned etch, the polymer film eventually peeled. In any case, these polymer masks can easily be removed in an oxygen plasma without adversely affecting device materials or structures.<<ETX>>}, booktitle={Proceedings of the Fourth International Conference on Indium Phosphide and Related Materials}, author={Schramm, J. E. and Yu, D.G. and Pekarik, J.J. and Hu, E.L. and Merz, J.}, year={1992}, pages={351} }