@article{mion_muth_preble_hanser_2006, title={Accurate dependence of gallium nitride thermal conductivity on dislocation density}, volume={89}, ISSN={["1077-3118"]}, DOI={10.1063/1.2335972}, abstractNote={The authors experimentally find that the thermal conductivity of gallium nitride depends critically on dislocation density using the 3-omega technique. For GaN with dislocation densities lower than 106cm−2, the thermal conductivity is independent with dislocation density. The thermal conductivity decreases with a logarithmic dependence for material with dislocation densities in the range of 107–1010cm−2. These results are in agreement with theoretical predictions. This study indicates that the hydride vapor phase epitaxy method offers an attractive route for the formation of semi-insulating gallium nitride with optimal thermal conductivity values around 230W∕mK and very low dislocation density near 5×104cm−2.}, number={9}, journal={APPLIED PHYSICS LETTERS}, author={Mion, C. and Muth, J. F. and Preble, E. A. and Hanser, D.}, year={2006}, month={Aug} }
 @article{mion_muth_preble_hanser_2006, title={Thermal conductivity, dislocation density and GaN device design}, volume={40}, ISSN={["0749-6036"]}, DOI={10.1016/j.spmi.2006.07.017}, abstractNote={The performance of high power transistor devices is intimately connected to the substrate thermal conductivity. In this study, the relationship between thermal conductivity and dislocation density is examined using the 3 omega technique and free standing HVPE GaN substrates. Dislocation density is measured using imaging cathodoluminescence. In a low dislocation density regime below 105 cm−2, the thermal conductivity appears to plateau out near 230 W/K m and can be altered by the presence of isotopic defects and point defects. For high dislocation densities the thermal conductivity is severely degraded due to phonon scattering from dislocations. These results are applied to the design of homoepitaxially and heteroepitaxially grown HEMT devices and the efficiency of heat extraction and the influence of lateral heat spreading on device performance are compared.}, number={4-6}, journal={SUPERLATTICES AND MICROSTRUCTURES}, author={Mion, C. and Muth, J. F. and Preble, Edward A. and Hanser, Drew}, year={2006}, pages={338–342} }
 @article{porter_mion_cai_zhang_muth_2005, title={Growth of ZnO films on C-plane (0001) sapphire by pulsed electron deposition (PED)}, volume={119}, ISSN={["0921-5107"]}, DOI={10.1016/j.mseb.2005.02.042}, abstractNote={Thin films of ZnO on C-plane (0 0 0 1) sapphire (α-Al2O3) substrates were grown by pulsed electron beam deposition (PED). Intense electron pulses, approximately 0.8 J/70 ns pulse produced by a channelspark pulsed electron source at a rate of 10 Hz were used to ablate sintered polycrystalline ZnO targets at an oxygen pressure of 15 mTorr. During growth, the sapphire substrate temperature was maintained at 700 °C. A 15 min growth produced a 250 nm film, as measured by a Dektak profilometer. Measurements by X-ray diffraction indicate c-axis oriented films. Cathodoluminescence (CL) data show strong band edge emission. Optical absorption data indicate a sharp band edge with clearly visible exciton absorption at room temperature, and resolved A and B excitons at 77 K. Thus, pulsed electron beam deposition of ZnO films is shown to be a viable technique for producing high quality ZnO films.}, number={2}, journal={MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY}, author={Porter, HL and Mion, C and Cai, AL and Zhang, X and Muth, JF}, year={2005}, month={May}, pages={210–212} }