Prof. Yuji Zhao

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Prof. Yuji Zhao

Office: ASU ECEE Rm. ERC 531 Email: [email protected] Phone: 480-727-4450

Publications

Book Chapters

  1. H. Chen, J. Zhou, H. Fu, and Y. Zhao, “Octave-Spanning Supercontinuum Generation in AlN Waveguides“, chapter in “Ultrawide Bandgap Semiconductors”, Volume 104, in the Semiconductors and Semimetals series, edited by Profs. Y. Zhao and Z, Mi, Elsevier, (2021).
  2. H. Fu, K. Fu, and Y. Zhao, “Vertical GaN-on-GaN Power Devices“, chapter in “Wide Bandgap Semiconductor-Based Electronics”, edited by Profs. F. Ren and S. J. Pearton, IOP Publishing (2020).
  3. H. Fu and Y. Zhao, “Efficiency droop in InGaN/GaN LEDs”, chapter in “Nitride Semiconductor Light-Emitting Diodes (LEDs)”, 2nd edition, edited by Profs. J. J. Huang, Prof. H. C. Kuo, and Prof. S. C. Shen, Woodhead Publishing, (2017).
  4. Y. R. Wu, C. Y. Huang, Y. Zhao, and J. S. Speck, “Nonpolar and Semipolar LEDs”, chapter in “Nitride Semiconductor Light-Emitting Diodes (LEDs)”, 1st edition, edited by Profs. J. J. Huang, H. C. Kuo, and S. C. Shen, Woodhead Publishing, (2014).

Journals

  1. H. Fu et al., “Vertical GaN power rectifiers and transistors: device principles and fabrication technologies”, submitted.
  2. C. Yang et al., “Low-leakage kV-class GaN vertical p–n diodes with non-destructive breakdown enabled by hydrogen-plasma termination with p-GaN extension”, submitted.
  3. K. Fu, et al., “Exploring the origin of Si contamination at GaN epitaxial regrowth interface and its impact for vertical GaN power device”, submitted.
  4. H. Fu, et al., “Selective area regrowth and doping for vertical GaN power devices: materials challenges and recent progress”, submitted.
  5. T. H. Yang, J. Brown, K. Fu, J. Zhou, K,. Hatch, C. Yang, J. Montes, X. Qi, H. Fu, R. J. Nemanich, and Y. Zhao, “AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MISHEMTs) using ERC-MPCVD deposited hexagonal boron nitride as gate dielectric”, accepted to Appl. Phys. Lett.
  6. P. Peri, K. Fu, H. Fu, Y. Zhao, and D. Smith, “Characterization of as-grown and regrown GaN-on-GaN heterostructures for vertical p-n power devices”, accepted to J. Electron. Mater.
  7. K. Fu, X. Qi, H. Fu, P. Y. Su, H. Liu, T. H. Yang, C. Yang, J. Montes, J. Zhou, F. Ponce, and Y. Zhao, “Characterization of MOCVD regrown p-GaN and the interface properties for vertical GaN power devices“, Semicond. Sci. Technol., vol. 36, 014005 (2020).
  8. A. Caria, C. De Santi, F. Zamperetti, X. Huang, H. Fu, H. Chen, Y. Zhao, A. Neviani, G. Meneghesso, E. Zanoni, M. Meneghini, “GaN-based high-periodicity multiple quantum well solar cells: degradation under optical and electrical stress”, Microelectron. Reliab., vol. 114, 113802 (2020).
  9. J. Montes, C. Kopas, H. Chen, X. Huang, T. H. Yang, K. Fu, C. Yang, J. Zhou, X. Qi, H. Fu, and Y. Zhao, “Deep level transient spectroscopy investigation of ultra-wide bandgap (-201) and (001) β-Ga2O3“, J. Appl. Phys., vol. 128, 205701 (2020).
  10. P. Peri, K. Fu, H. Fu, Y. Zhao, and D. J. Smith, “Structural breakdown in GaN-on-GaN high power p-n diode devices stressed to failure“, J. Vac. Sci. Technol. A., vol. 38, 063408 (2020). Highlight as “Editor’s Pick” in JVSTA & Selected as “Scilight” in AIP.
  11. P. Y. Su, H. Liu, C. Yang, K. Fu, H. Fu, Y. Zhao, and F. A. Ponce, “Lateral and vertical growth of Mg-doped GaN on trench-patterned GaN films“, Appl. Phys. Lett., vol. 117, 102110 (2020).
  12. C. Yang, H. Fu, V. N. Kumar, K. Fu, H. Liu, X. Huang, T. H. Yang, H. Chen, J. Zhou, X. Deng, J. Montes, F. A. Ponce, D. Vasileska, and Y. Zhao, “GaN vertical-channel junction field-effect transistors with regrown p-GaN by MOCVD“, IEEE Trans. Electron Devices, vol. 67, 3972 (2020).
  13. G. Moses, X. Huang, Y. Zhao, M. Auf Der Maur, E. A. Katz, and J. M. Gordon,”InGaN/GaN multi-quantum-well solar cells under high solar concentration and elevated temperatures for hybrid solar thermal-photovoltaic power plants“, Prog. Photovolt. Res. Appl., vol. 28, 1167 (2020).
  14. C. Yang, H. Fu, P. Y. Su, H. Liu, K. Fu, X. Huang, T. H. Yang, H. Chen, J. Zhou, X. Deng, J. Montes, X. Qi, F. Ponce, and Y. Zhao.”Demonstration of GaN-based metal-insulator-semiconductor junction by hydrogen plasma treatment“, Appl. Phys. Lett., vol. 117, 052105 (2020).
  15. T. H. Yang, H. Fu, K. Fu, C. Yang, J. Montes, X. Huang, H. Chen, J. Zhou, X. Qi, X. Deng, and Y. Zhao, “Vertical GaN-on-GaN Schottky barrier diodes with multi-floating metal rings“, IEEE J. Electron Devices Soc., vol. 8, 857 (2020).
  16. J. He, H. Chen, J. Hu, J. Zhou, Y. Zhang, A. Kovach, C. Sideris, M. C. Harrison, Y. Zhao, and A. M. Armani, “Nonlinear Nanophotonics devices in the ultraviolet to visible wavelength range“, Nanophotonics, vol. 9, 3781 (2020). Invited Review.
  17. X. Huang, D. Li, P. Y. Su, H. Fu, H. Chen, C. Yang, J. Zhou, X. Qi, T. H. Yang, J. Montes, X. Deng, K. Fu, S. P. DenBaars, S. Nakamura, F. A. Ponce, C. Z. Ning, and Y. Zhao, “Anomalous carrier dynamics and localization effects in nonpolar m-plane InGaN/GaN quantum wells at high temperatures“, Nano Energy, vol. 76, 105013 (2020).
  18. B. Raghothamachar, Y. Liu, H. Peng, T. Ailihumaer, M Dudley, F. S. Shahedipour-Sandvik, K. A. Jones, A. Armstrong, A. A. Allerman, J. Han, H. Fu, K. Fu, and Y. Zhao, “X-ray topography characterization of gallium nitride substrates for power device development“, J. Cryst. Growth, vol. 544, 125709 (2020).
  19. K. Song, H. Zhang, H. Fu, C. Yang, R. Singh, Y. Zhao, H. Sun, and S. Long, “Normally-off AlN/β-Ga₂O₃ field-effect transistors using polarization-induced doping“, J. Phys. D., vol. 53, 345107 (2020).
  20. K. Fu, H. Fu, X. Huang, T. H. Yang, C. Y. Cheng, P. R. Peri, H. Chen, J. Montes, C. Yang, J. Zhou, X. Deng, X. Qi, D. J. Smith, S. M. Goodnick, and Y. Zhao, “Reverse leakage analysis for as-grown and regrown vertical GaN-on-GaN Schottky barrier diodes”, IEEE J. Electron Devices Soc., vol. 8, 74 (2020).
  21. H. Fu, K. Fu, S. R. Alugubelli, C. Y. Cheng, X. Huang, H. Chen, T. H. Yang, C. Yang, J. Zhou, J. Montes, X. Deng, X. Qi, S. Goodnick, F. A. Ponce, and Y. Zhao, “High voltage vertical GaN p-n diodes with hydrogen-plasma based guard rings“, IEEE Electron Device Lett., vol. 41, 127 (2020). Most popular articles in IEEE Electron Device Lett. in December 2019 and January 2020.
  22. J. Zhou, H. Chen, H. Fu, K. Fu, X. Deng, X. Huang, T. H. Yang, J. A. Montes, C. Yang, X. Qi, B. Zhang, X. Zhang, and Y. Zhao, “Demonstration of low loss β-Ga2O3 optical waveguides in the UV-NIR Spectra“, Appl. Phys. Lett., vol. 115, 251108 (2019).
  23. S. R. Alugubelli, H. Fu, K. Fu, H. Liu, Y. Zhao, M. R. McCartney, and F. A. Ponce, “Determination of electronic band structure by electron holography of etched-and- regrown interfaces in GaN p-i-n diodes”, Appl. Phys. Lett., vol. 115, 201602 (2019).
  24. H. Chen, J. Zhou, D. Li, D. Chen, A. K. Vinod, H. Fu, X. Huang, T. H. Yang, J. Montes, K. Fu, C. Yang, C. Z. Ning, C. W. Wong, A. M. Armani, and Y. Zhao, “On-chip directional octave-spanning supercontinuum generation from high order mode in near ultraviolet to infrared spectrum using AlN waveguides”, arXiv: 1908.04719. 
  25. K. Fu, H. Fu, X. Huang, H. Chen, T. H. Yang, J. Montes, C. Yang, J. Zhou, and Y. Zhao, “Demonstration of 1.27 kV etched-then-regrown GaN-on-GaN vertical p-n junctions with low leakage current for GaN power electronics“, IEEE Electron Device Lett., vol. 40, 1728 (2019). Most popular articles in IEEE Electron Device Lett. in November 2019.
  26. X. Huang, W. Li, H. Fu, D. Li, Dongying, C. Zhang, H. Chen, Y. Fang, K. Fu, S. DenBaars, S. Nakamura, S. Goodnick, C. Z. Ning, S. Fan, and Y. Zhao, “High temperature polarization-free III-nitride solar cells with self-cooling effects”, ACS Photonics, vol. 6, 2096 (2019).
  27. S. R. Alugubelli, H. Fu, K. Fu, H. Liu, Y. Zhao, and F. A. Ponce “Dopant profiling in p-i-n GaN structures using secondary electrons“,  J. Appl. Phys., vol. 126, 015704 (2019).
  28. H. Chen, H. Fu, J. Zhou, X. Huang, T. H. Yang, K. Fu, C. Yang, J. A. Montes, and Y. Zhao, “Study of crystalline defect induced optical scattering loss inside protonic waveguides in UV-visible spectral wavelengths using volume current method“, Opt. Express, vol. 27, 17262 (2019). 
  29. H. Fu, K. Fu, H. Liu, S. Alugubelli, X. Huang, H. Chen, J. Montes, T. H. Yang, C. Yang, J. Zhou, F. A. Ponce, and Y. Zhao, “Implantation- and etching-free high voltage vertical GaN p-n diodes terminated by plasma-hydrogenated p-GaN: Revealing the role of thermal annealing“, Appl. Phys. Express, vol. 12 051015 (2019). Highlight in Applied Physics Express Spotlights 2019.
  30. J. Montes, C. Yang, H. Fu, T. H. Yang, K. Fu, H. Chen, J. Zhou, X. Huang, and Y. Zhao, “Demonstration of mechanically exfoliated β-Ga2O3/GaN p-n heterojunction“, Appl. Phys. Lett., vol. 114, 162103 (2019).
  31. H. Liu, H. Fu, K. Fu, S. R. Alugubelli, P. Y. Su, Y. Zhao, and F. A. Ponce, “Non-uniform Mg distribution in GaN epilayers grown on mesa structures for applications in GaN power electronics“, Appl. Phys. Lett., vol. 114, 082102 (2019). 
  32. X. Huang, R. Fang, C. Yang, K. Fu, H. Fu, H. Chen, T. H. Yang, J. Zhou, J. Montes, M. Kozicki, H. Barnaby, B. Zhang, and Y. Zhao, “Steep-slope AlGaN/GaN HEMT with oxide based threshold switching device”, Nanotechnology, vol. 30, 215201 (2019).
  33. K. Fu, H. Fu, X. Huang, T. H. Yang, H. Chen, I. Baranowski, J. Montes, C. Yang, J. Zhou, and Y. Zhao, “Threshold switching and memory behaviors of epitaxially regrown GaN-on-GaN vertical p-ndiodes with high temperature stability“, IEEE Electron Device Lett., vol. 40, 375 (2019). Highlight on IEEE EDL Journal Cover. News report by IEEE Spectrum, Compound Semiconductor, etc.
  34. J. Montes, T. H. Yang, H. Fu, H. Chen, X. Huang, K. Fu, I. Baranowski, and Y. Zhao, “Effect of proton radiation on ultra-wide bandgap AlN Schottky barrier diodes“, IEEE Trans. Nucl. Sci., vol. 66, 91 (2019).
  35. T. H. Yang, H. Fu, H. Chen, X. Huang, J. Montes, I. Baranowski, K. Fu, and Y. Zhao, “Temperature-dependent electrical properties of β-Ga2O3 Schottky barrier diodes on highly doped single-crystal substrates and their reverse current leakage mechanisms“, J. Semicond., vol. 40, 012801 (2019). Invited Paper.
  36. K. Fu, H. Fu, H. Liu, S. R. Alugubelli, T. H. Yang, X. Huang, H. Chen, I. Baranowski, J. Montes, F. A. Ponce, and Y. Zhao, “Investigation of GaN-on-GaN vertical p-n diode with regrown p-GaN by metal organic chemical vapor deposition“, Appl. Phys. Lett., vol. 113, 233502 (2018). 
  37. H. Fu, X. Zhang, K. Fu, H. Liu, S. R. Alugubelli, X. Huang, H. Chen, I. Baranowski, T. H. Yang, K. Xu, F. A. Ponce, B. Zhang, and Y. Zhao, “Novel vertical GaN-on-GaN p-n diodes grown on free-standing (10-10) m-plane GaN substrates“, Appl. Phys. Express, vol. 11, 111003 (2018).
  38. Z. Lu, P. Tian, H. Fu, J. Montes, X. Huang, H. Chen, X. Zhang, X. Liu, R. Liu, L. Zheng, X. Zhou, E. Gu, Y. Liu, and Y. Zhao, “Experimental demonstration of non-line-of-sight visible light communication using a GaN-based micro-LED and practical IEEE 802.11ac“, AIP Adv., vol. 8, 105017 (2018). 
  39. X. Huang, H. Chen, H. Fu, I. Baranowski, J. Montes, T. H. Yang, K. Fu, B. P. Gunning, D. D. Koleske, and Y. Zhao, “Energy band engineering of InGaN/GaN multi-quantum-well solar cells via AlGaN electron- and hole-blocking layers“, Appl. Phys. Lett., vol. 113, 043501 (2018). 
  40. H. Fu, K. Fu, X. Huang, H. Chen, I. Baranowski, T. H. Yang, J. Montes, and Y. Zhao, “High performance vertical GaN-on-GaN p-n power diodes with hydrogen-plasma based edge termination“, IEEE Electron Device Lett., vol. 39, 1018 (2018). 
  41. H. Fu, H. Chen, X. Huang, I. Baranowski, J. Montes, T. H. Yang, and Y. Zhao,”A comparative study on the electrical properties of vertical (-201) and (010) β-Ga2O3 Schottky barrier diodes on EFG single-crystal substrates“, IEEE Trans. Electron Devices, vol. 65, 3507 (2018). 
  42. H. Chen, X. Huang, J. A. Montes, T. H. Yang, I. Baranowski, and Y. Zhao, “Characterizations of the nonlinear optical properties for (010) and (-201) beta-phase gallium oxide“, Opt. Express, vol. 26, 3938 (2018). 
  43. Y. Zhao, H. Fu, G. T. Wang, and S. Nakamura, “Toward ultimate efficiency: progress and prospects on planar and 3D nanostructured nonpolar and semipolar InGaN light emitting diodes” Adv. Opt. Photonics, vol. 10, 246 (2018). Highlight in ASU News.
  44. H. Chen, H. Fu, X. Huang, X. Zhang, T. H. Yang, J. A. Montes, I. Baranowski, and Y. Zhao, “Low loss GaN waveguides at the visible spectral wavelengths for integrated photonics applications“, Opt. Express., vol. 25, 31758 (2017). 
  45. X. Huang, H. Fu, H. Chen, Z. Lu, I. Baranowski, J. Montes, T. H. Yang, B. P. Gunning, D. Koleske, and Y. Zhao, “Reliability analysis of InGaN/GaN multi-quantum-well (MQW) solar cells under thermal stress“, Appl. Phys. Lett., vol. 111, 233511 (2017). 
  46. H. Fu, X. Huang, H. Chen, Z. Lu, I. Baranowski, and Y. Zhao, “Ultra-low turn-on voltage and on-resistance vertical GaN-on-GaN Schottky power diodes with high mobility double drift layers“, Appl. Phys. Lett., vol. 111, 152102 (2017). Highlight in Silicon Valley Microelectronics, Semiconductor Today, etc.
  47. H. Y. Huang, Y. Fan, Z. Lu, T. Luo, H. Fu,  H. Song, Y. Zhao, and J. B. Christen, “Variable self-powered light detection CMOS chip with real-time adaptive tracking digital output based on a novel on-chip sensor“, Opt. Express, vol. 25, 24138 (2017).
  48. H. Fu, X. Huang, H. Chen, Z. Lu, and Y. Zhao, “Fabrication and characterization of ultra-wide bandgap AlN based Schottky diodes on sapphire by MOCVD“, IEEE J. Electron Devices Soc., vol. 5, 518 (2017). Top 50 most popular articles in October 2017 and January 2018 in JEDS.
  49. Z. Lu, P. Tian, H. Chen, I. Baranowski, H. Fu, X. Huang, J. Montes, Y. Fan, H. Wang, X. Liu, R. Liu, and Y. Zhao, “Active tracking system for visible light communication using a GaN-based micro-LED and NRZ-OOK“, Opt. Express, vol. 25, 17971 (2017).
  50. H. Fu, X. Zhang, X. Huang, I. Baranowski, H. Chen, Z. Lu, J. Montes, and Y. Zhao, “Demonstration of AlN Schottky barrier diodes with blocking voltage over 1kV“, IEEE Electron Device Lett., vol. 38, 1286 (2017).  Highlight in Silicon Valley Microelectronics, Semiconductor Today, etc. Top 50 most popular articles in August and September 2017 in IEEE EDL.
  51. H. Chen, X. Huang, H. Fu, Z. Lu, X. Zhang, J. A. Montes, and Y. Zhao “Characterizations of nonlinear optical properties on GaN crystals in polar, nonpolar, and semipolar orientations“, Appl. Phys. Lett., vol. 110, 181110 (2017). 
  52. H. Fu, X. Huang, H. Chen, Z. Lu, X. Zhang, and Y. Zhao, “Effect of buffer layer design on vertical GaN-on-GaN p-n and Schottky power diodes“,  IEEE Electron Device Lett., vol. 38, 763 (2017).  Highlight in Silicon Valley Microelectronics, Semiconductor Today, etc. Top 50 most popular articles in April, Mary and June 2017 in IEEE EDL.
  53. X. Huang, H. Fu, H. Chen, X. Zhang, Z. Lu, J. Montes, M. Iza, S. P. DenBaars, S. Nakamura, and Y. Zhao,  “Nonpolar and semipolar InGaN/GaN multiple-quantum-well solar cells with improved carrier collection efficiency“, Appl. Phys. Lett., vol. 110, 161105 (2017). Highlight in Semiconductor Today.
  54. H. Chen, H. Fu, X. Huang, Z. Lu, X. Zhang, J. Montes, and Y. Zhao, “Optical cavity effects in InGaN core-shell light-emitting diodes with metallic coating“, IEEE Photonics J., vol. 9, 8200828 (2017).
  55. H. Fu, H. Chen, X. Huang, Z. Lu,  and  Y. Zhao, “Theoretical analysis of modulation doping effects on intersubband transition properties of semipolar AlGaN/GaN quantum well“, J. Appl. Phys., vol. 121, 014501 (2017).
  56. H. Fu, Z. Lu,  and  Y. Zhao,  “Analysis of low efficiency droop of semipolar InGaN quantum well light-emitting diodes by modified rate equation with weak phase-space filling effect“, AIP Adv., vol. 6, 065013 (2016).
  57. X. Huang, H. Fu, H. Chen, Z. Lu, D. Ding, and  Y. Zhao,  “Analysis of loss mechanisms in InGaN solar cells using a semi-analytical model“, J. Appl. Phys., vol. 119, 213101 (2016).
  58. H. Fu, Z. Lu, X. Huang, H. Chen, and  Y. Zhao,  “Crystal orientation dependent Intersubband transition in semipolar AlGaN/GaN single quantum well for optoelectronic applications“, J. Appl. Phys., vol. 119, 174502 (2016).
  59. H. Chen, H. Fu, Z. Lu, X. Huang, and  Y. Zhao,  “Optical properties of highly polarized InGaN light-emitting diodes modified by plasmonic metallic grating“, Opt. Express, vol. 24, A856 (2016).
  60. H. Fu, Z. Lu, X. Zhao, Y. H. Zhang, S. P. DenBaars, S. Nakamura, and  Y. Zhao,  “Study of low efficiency droop in semipolar (20-2-1) InGaN light-emitting diodes by time-resolved photoluminescence“, J. Display Technol., vol. 12, 736 (2016).
  61. R.Ivanov, S. Marcinkevicius, Y. Zhao, D. L. Becerra, S. Nakamura, S. P. DenBaars, and J. S. Speck,  “Impact of carrier localization on radiative recombination times in semipolar (20-21) InGaN/GaN quantum wells“, Appl. Phys. Lett., vol. 107, 211109 (2015).
  62. J. Xue, Y. Zhao, S. H. Oh, J. S. Speck, S. P. DenBaars, S. Nakamura, and R. J. Ram, “Thermally enhanced blue light-emitting diodes“, Appl. Phys. Lett., vol. 107, 121109 (2015). Highlight in Nature Photonics.
  63. C. C. Pan, Q. Yan, H. Fu, Y. Zhao, Y. R. Wu, C. G. Van de Walle, S. Nakamura, and S. P. DenBaars, “High optical power and low efficiency droop blue light-emitting diodes using compositionally step-graded InGaN barrier“, Electron. Lett., vol. 51, pp. 1187 – 1189 (2015). 
  64. K. Gelzinyte, S Marcinkevicius, Y. Zhao, D. L. Becerra, S. Nakamura, S. P. DenBaars, and J. S. Speck,  “High spatial uniformity of photoluminescence spectra in semipolar (20-21) plane InGaN/GaN quantum wells“, J. Appl. Phys., vol. 117, 023111 (2015). 
  65. D. L. Becerra, Y. Zhao, S. H. Oh, C. D. Pynn, K. Fujito, S. P. DenBaars, and S. Nakamura, “High-power low-droop violet semipolar (30-3-1) InGaN/GaN light-emitting diodes with thick active layer design“,  Appl. Phys. Lett., vol. 105, 171106 (2014). Highlight in Semiconductor Today.
  66. Y. Zhao, R. M. Farrell, Y. R. Wu, and J. S. Speck, “Valence band states and polarized optical emission from nonpolar and semipolar III–nitride quantum well optoelectronic devices”,  Jpn. J. Appl. Phys. Selected Topics in Applied Physics, vol. 53, 100206 (2014). Invited paper.
  67. S. Marcinkevicius, K. Gelzinyte, Y. Zhao, S. Nakamura, S. P. DenBaars, and J. S. Speck, “Carrier distributation between different potential cites in semipolar quantum well studied by near-field photoluminescence“, Appl. Phys. Lett., vol. 105, 111108 (2014). 
  68. F. Wu, Y. Zhao, A. Romanov, S. P. DenBaars, S. Nakamura, and J. S. Speck, “Stacking faults and interface roughening in semipolar (20-2-1) single InGaN quantum wells for long wavelength emission”, Appl. Phys. Lett., vol. 104, 151901 (2014). 
  69. Y. Ji, W. Liu, T. Erdem, R. Chen, S. T. Tan, Z. H. Zhang, Z. Ju, X. Zhang, H. Sun, X. W. Sun, Y. Zhao, S. P. DenBaars, S. Nakamura, and H. V. Demir, “Comparative study of field-dependent carrier dynamics and emission kinetics of InGaN/GaN light-emitting diodes grown on (11-22) semipolar versus (0001) polar planes”, Appl. Phys. Lett., vol. 104, 143506 (2014). 
  70. S. Marcinkevicius, R. Ivanov, Y. Zhao, S. Nakamura, S. P. DenBaars, and J. S. Speck, “Highly polarized photoluminescence and its dynamics in semipolar (20-2-1) InGaN/GaN quantum well”, Appl. Phys. Lett., vol. 104, 111113 (2014). 
  71. Y. Zhao, F. Wu, T. J. Yang, Y. R. Wu, S. Nakamura, and J. S. Speck, “Atomic scale nanofacet structure in semipolar InGaN single quantum well”, Appl. Physics Express, vol. 7, 025503 (2014). 
  72. M. T. Hardy, F. Wu, C. Y. Huang, Y. Zhao, D. Feezell, J. S. Speck, S. Nakamura, and S. P. DenBaars, “Impact of p-GaN temperature and AlGaN barrier composition on (20-21) green laser diodes”, IEEE Photonics Technol. Lett., vol. 26, 43 (2014). 
  73. S. Marcinkevicius, Y. Zhao, K. M. Kelchner, S. Nakamura, S. P. DenBaars, and J. S. Speck, “Near-field investigation of spatial variations of (20-2-1) InGaN quantum well emission spectra”, Appl. Phys. Lett., vol. 102, 131116 (2013). 
  74. Y. Zhao, S. H. Oh, F. Wu, Y. Kawaguchi, S. Tanaka, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Green semipolar (20-2-1) InGaN light-emitting diodes with small wavelength shift and narrow spectral width”, Appl. Phys. Express, vol. 6, 062102 (2013). Highlight in Nature Photonics, vol. 7 585 (2013), Compound Semiconductor, etc & “Research Highlights” on front page of APEX & Top 20 most downloaded articles May to July 2013 in APEX.
  75. Y. Kawaguchi, S. C. Huang, R. M. Farrell, Y. Zhao, J .S. Speck, S. P. DenBaars, and S. Nakamura, “Dependence of electron overflow on emission wavelength and crystallographic orientation in single-quantum-well III-nitride light-emitting diodes”, Appl. Phys. Express, vol. 6, 052103 (2013). “Research Spotlights” & Top 20 most downloaded articles April and June 2013 in APEX.
  76. Y. Zhao, F. Wu, C. Y. Huang, Y. Kawaguchi, S. Tanaka, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Suppressing the void defects in the long wavelength semipolar InGaN quantum wells by growth rate optimization”, Appl. Phys. Lett., vol. 102, 091905 (2013). 
  77. S. P. DenBaars, D. Feezell, K. Kelchner, S. Pimputkar, C. C. Pan, C. C. Yen, S. Tanaka, Y. Zhao, N. Pfaff, R. Farrell, M. Iza, S. Keller, U. Mishra, J. S. Speck, and S. Nakamura, “Development of gallium-nitride-based light-emitting diodes (LEDs) and laser diodes for energy efficient lighting and displays”, Acta Mater., vol. 61, 945 (2013). (Invited) 
  78. Y. Zhao, Q. Yan, D. Feezell, K. Fujito, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Optical polarization characteristics of semipolar (30-31) and (30-3-1) InGaN/GaN light-emitting diodes”, Opt. Express, vol. 21, A53 (2013).
  79. Y. Kawaguchi, C. Y. Huang, Y. R. Wu, Y. Zhao, S. P. DenBaars, and S. Nakamura, “Semipolar 20-21 single-quantum-well red light-emitting diodes with a low forward voltage”, Jpn. J. Appl. Phys., vol. 52, 08JC08 (2013). 
  80. C. C. Pan, T. Gilberto, N. Pfaff, S. Tanaka, Y. Zhao, D. Feezell, J. S. Speck, S. Nakamura, and S. P. DenBaars, “Reduction in thermal droop using thick quantum well structure in semipolar (20-2-1) blue light-emitting diodes”, Appl. Phys. Express, vol. 5, 102103 (2012). 
  81. Y. Kawaguchi, C. Y. Huang, Y. R. Wu, Q. Yen, C. C. Pan, Y. Zhao, S. Tanaka, K. Fujito, D. Feezell, C. G. Van de Walle, S. P. DenBaars, and S. Nakamura, “Influence of polarity on carrier transport in semipolar (20-2-1) and (20-21) multiple-quantum-well light-emitting diodes”, Appl. Phys. Lett., vol. 100, 231110 (2012). “APL Editor’s Picks of the Year Award” in 2012 &“Research Highlights” of AIP June 2012 & “Editor’s Choice” in the AIP Virtual Journal of Nanoscience and Technology, Vol. 25(25), June 2012 & Top 20 most downloaded articles June 2012 in APL.
  82. C. C. Pan, S. Tanaka, F. Wu, Y. Zhao, J. S. Speck, S. Nakamura, S. P. DenBaars, and D. Feezell, “High-power, low-efficiency-droop (20-2-1) single-quantum-well blue light-emitting diodes”, Appl. Phys. Express, vol. 5, 062103 (2012). Top 20 most downloaded articles June and July 2012 in APEX. “Research Highlights” on front page of APEX & Top 20 most downloaded articles September and October 2012 in APEX.
  83. Y. Zhao, Q. Yan, C. Y. Huang, S. C. Huang, P. S. Hsu, S. Tanaka, C. C. Pan, Y. Kawaguchi, K. Fujito, D. Feezell, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Indium incorporation and emission properties of nonpolar and semipolar InGaN quantum wells”, Appl. Phys. Lett., vol. 100, 201108 (2012). 
  84. J. J. Richardson, I. Koslow, C. C. Pan, Y. Zhao, J. S. Ha, and S. DenBaars, “Semipolar single-crystal ZnO films deposited by low-temperature aqueous solution phase epitaxy on GaN light-emitting diodes”, Appl. Phys. Express, vol. 4, 126502 (2011). Top 20 most downloaded articles December 2011 in APEX.
  85. C. Y. Huang, Q. Yan, Y. Zhao, D. Feezell, K. Fujito, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Influence of Mg-doped barriers on semipolar multi-quantum-well light-emitting diodes”, Appl. Phys. Lett., vol. 99, 141114 (2011). 
  86. Y. Zhao, S. Tanaka, Q. Yan, C. Y. Huang, R. B. Chung, C. C. Pan, K. Fujito, D. Feezell, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “High optical polarization ratio from semipolar (20-2-1) blue-green InGaN/GaN light-emitting diodes”, Appl. Phys. Lett., vol. 99, 051109 (2011). 
  87. Y. Zhao, S. Tanaka, C. C. Pan, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “High-power blue-violet semipolar (20-2-1) InGaN/GaN light-emitting diodes with low efficiency droop at 200 A/cm2”, Appl. Phys. Express, vol. 4, 082104 (2011). Highlight in Science, Optical Society of America, Semiconductor Today, etc. “Most Cited APEX Articles of the Year Award” in 2012 & Top 20 most downloaded articles July 2011 in APEX.
  88. S. Tanaka, Y. Zhao, I. Koslow, C. C. Pan, H. T. Chen, J. Sonoda, S. P. DenBaars, and S. Nakamura, “Droop improvement in high current range on PSS-LEDs”, Electron. Lett., vol. 47, pp. 335 – 336 (2011). 
  89. S. Yamamoto, Y. Zhao, C. C. Pan, R. B. Chung, K. Fujito, J. Sonoda, S. P. DenBaars, and S. Nakamura, “High-efficiency single-quantum-well green and yellow-green light-emitting diodes on semipolar (20-21) GaN substrates”, Appl. Phys. Express,vol. 3, 122102 (2010). Top 20 most downloaded articles November and December 2010 in APEX.
  90. Y. Zhao, J. Sonoda, C. C. Pan, S. Brinkley, I. Koslow, H. Ohta, S. P. DenBaars, and S. Nakamura, “30-mW-class high-power and high-efficiency blue semipolar (10-1-1) InGaN/GaN light-emitting diodes obtained by backside roughening technique”, Appl. Phys. Express, vol. 3, 102101 (2010). Highlight in Laser Focus World, Photonics, etc & Top 20 most downloaded articles September and October 2010 in APEX.
  91. Y. Zhao, J. Sonada, I. Koslow, C. C. Pan, H. Ohta, J. S. Ha, S. P. DenBaars, and S. Nakamura, “Optimization of device structure for bright blue semipolar (10-1-1) light emitting diodes via metalorganic chemical vapor deposition”, Jpn. J. Appl. Phys., vol. 49, 070206 (2010). Highlight in Semiconductor Today, etc. Top 20 most downloaded articles July and August 2010 in JJAP.

Conferences (Refereed)

  1.  A. Caria, C. De Santi, F. Zamperetti, X. Huang, H. Fu, H. Chen, Y. Zhao, G. Meneghesso, E. Zanoni, and M.Meneghini, “GaN-based high-periodicity multiple quantum well solar cells: degradation under optical and electrical stress”, The 31st European Symposium on Reliability of Electron Devices, Failure Physics and Analysis (ESREF 2020), Oct 2020, Athens, Greece, Oral Presentation.
  2. P. R. Peri, K. Hatch, D. Messina, K. Fu, Y. Zhao, R. Nemanich, and D. Smith,”Plasma enhanced atomic layer-etched and regrown GaN-on-GaN high power p-n diodes”, 2020 Microscopy & Microanalysis Meeting (M&M 2020), Aug 2020, Milwaukee, WI, Oral Presentation.
  3. J. Montes, H. Fu, H. Chen, X. Huang, T. H. Yang, K. Fu, C. Yang, J. Zhou, X. Qi, X. Deng, and Y. Zhao, “Examining deep-level defects in (-201) β-Ga2O3 by deep level transient spectroscopy”, The 62rd Electronic Materials Conference (EMC 2020), June 2020, Columbus, OH, Oral Presentation.
  4. K. Fu, H. Fu, X. Huang, H. Chen, T. H. Yang, J. Montes, C. Yang, J. Zhou, X. Qi, X. Deng, and Y. Zhao, “1.27 kV etch-then-regrow GaN p-n junctions with low leakage for GaN power electronics”, The 62rd Electronic Materials Conference (EMC 2020), June 2020, Columbus, OH, Oral Presentation.
  5. T. H. Yang, H. Fu, K. Fu, C. Yang, J. Montes, X. Huang, H. Chen, J. Zhou, and Y. Zhao, “The investigation of vertical GaN Schottky barrier diode with floating metal guard rings”, The 62rd Electronic Materials Conference (EMC 2020), June 2020, Columbus, OH, Oral Presentation.
  6. X. Huang, D. Li, P. Su, H. Fu, H. Chen, K. Fu, T. H. Yang, J. Montes, C. Yang, J. Zhou, X. Qi, X. Deng, S. P. DenBaars, S. Nakamura, F. Ponce, C. Z. Ning, and Y. Zhao, “Carrier localization and dynamics of nonpolar m-plane InGaN/GaN MQWs at elevated temperatures”, The 62rd Electronic Materials Conference (EMC 2020), June 2020, Columbus, OH, Oral Presentation.
  7. H. Fu, K. Fu, S. R. Alugubelli, C. Y. Cheng, X. Huang, H. Chen, T. H. Yang, C. Yang, J. Zhou, J. Montes, X. Deng, X. Qi, S. M. Goodnick, F. A. Ponce, and Y. Zhao, “Novel Hydrogen-Plasma based Guard Rings for High-Voltage Vertical GaN-on-GaN p-n Diodes”, The 62rd Electronic Materials Conference (EMC 2020), June 2020, Columbus, OH, Poster Presentation.
  8. J. Zhou, H. Chen, H. Fu, K. Fu, X. Deng, X. Huang, T. H. Yang, J. A. Montes, C. Yang, X. Qi, B. Zhang, X. Zhang, and Y. Zhao, “Demonstration of low loss β-Ga2O3 optical waveguides in the UV–NIR spectra”, 2020 CLEO, May 2020, San Jose, CA, Poster Presentation. Online form due to COVID-19.
  9. H. Fu, K. Fu, C. Yang, H. Liu, K. A. Hatch, S. R. Alugubelli, P. Y. Su, D. C. Messina, X. Deng, B. Li, P. R. Peri, C. Y. Cheng, X. Huang, H. Chen, D. J. Smith, S. M. Goodnick, E. T. Yu, J. Han, R. J. Nemanich, F. A. Ponce, and Y. Zhao, “Recent progress on selective area regrowth and doping for vertical GaN power transistors”, 2020 Compound Semiconductor Week (CSW 2020) and the 47th International Symposium on Compound Semiconductors (ISCS 2020), May 2020, Stockholm, Sweden, Oral Presentation. Canceled due to COVID-19.
  10. C. Yang, H. Fu, V. N. Kumar, K. Fu, H. Liu, X. Huang, J. Montes, T. H. Yang, H. Chen, J. Zhou, X. Deng, F. A. Ponce, D. Vasileska, and Y. Zhao, “Normally-off GaN vertical-channel junction field-effect transistors with regrown p-GaN by MOCVD”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Oral Presentation. Canceled due to COVID-19.
  11. J. Montes, H. Fu, H. Chen, X. Huang, T. H. Yang, K. Fu, C. Yang, J. Zhou, X. Qi, X. Deng, and Y. Zhao, “Examining deep-level defects in (-201) β-Ga2O3 by deep level transient spectroscopy”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Oral Presentation. Canceled due to COVID-19.
  12. H. Fu, K. Fu, S. R. Alugubelli, C. Y. Cheng, X. Huang, H. Chen, T. H. Yang, C. Yang, J. Zhou, J. Montes, X. Deng, X. Qi, S. M. Goodnick, F. A. Ponce, and Y. Zhao, “KV-class GaN power o-n diodes with plasma-based guard rings”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Oral Presentation. Canceled due to COVID-19.
  13. J. Zhou, H. Chen, H. Fu, K. Fu, X. Deng, X. Huang, T. H. Yang, J. A. Montes, C. Yang, X. Qi, B. Zhang, X. Zhang, and Y. Zhao, “Demonstration of low loss β-Ga2O3 optical waveguides in the UV–visible spectra”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Oral Presentation. Canceled due to COVID-19.
  14. X. Huang, D. Li, H. Fu, P. Su, H. Chen, K. Fu,  S. P. DenBaars, S. Nakamura, F. Ponce, C. Z. Ning, and Y. Zhao, “High temperatures carrier dynamics of nonpolar InGaN/GaN MQWs”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Poster Presentation. Canceled due to COVID-19.
  15. K. Fu, H. Fu, X. Huang, H. Chen, T. H. Yang, J. Montes, C. Yang, J. Zhou, X. Qi, X. Deng, and Y. Zhao, “Etch-then-regrow vertical GaN p-n diodes with high breakdown voltage and low leakage current”, 2020 MRS Spring Meeting, Apr 2020, Phoenix, AZ, Poster Presentation. Canceled due to COVID-19.
  16. A. Caria, C. De Santi, X. Huang, H. Fu, H. Chen, Y. Zhao, G. Meneghesso, E. Zanoni, M.Meneghini, “Degradation and recovery of high-periodicity InGaN/GaN MQWs under optical stress in short-circuit condition”, SPIE Photonics West 2020, Feb 2020, San Francisco, CA, Oral Presentation.
  17. X. Huang, H. Fu, and Y. Zhao, “High performance nonplar m-plane InGaN multiple-quantum-well solar cells with improved carrier collection and high temperature spectral response”, 2019 ASME International Technical Conference on Packaging and Integration of Electronic and Photonic Microsystems (ASME InterPACK 2019), Oct 2019, Anaheim, CA.
  18. P. Peri, K. Fu, Y. Zhao, and D. J. Smith, “Characterization of etched and grown GaN-GaN Schottky diodes”, 2019 Microscopy & Microanalysis Meeting (M&M 2019), Aug 2019, Portland, OR.
  19. H. Fu, K. Fu, H. Liu, S. R. Alugubelli, F. A. Ponce, and Y. Zhao, “Effective selective area doping for GaN vertical power transistors enabled by epitaxial regrowth”, The 19th International Conference on Crystal Growth and Epitaxy (ICCGE-19) and the 19th US Biennial Workshop on Organometallic Vapor Phase Epitaxy (OMVPE-19), Jul 2019, Keystone, CO, Oral Presentation.
  20. H. Chen, H. Fu, X. Huang, J. Zhou, T. H. Yang, K. Fu, J. Montes, C. Yang, and Y. Zhao, “Supercontinuum generation from dispersion engineered AlN waveguide arrays”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  21. H. Fu, K. Fu, H. Liu, S. R. Alugubelli, X. Huang, H. Chen, J. Montes, T. H. Yang, C. Yang, J. Zhou, F. A. Ponce, and Y. Zhao, “High voltage implantation-free vertical GaN power p-n diodes with a novel low-temperature plasma-based planar edge termination”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  22. K. Fu, H. Fu, X. Huang, T. H. Yang, H. Chen, J. Montes, C. Yang, J. Zhou, and Y. Zhao. “Threshold switching and memory behaviors of GaN-on-GaN regrown vertical p-n diodes with high temperature stability”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  23. C. Yang, J. Montes, H. Fu, T. H. Yang, K. Fu, H. Chen, J. Zhou, X. Huang, and Y. Zhao, “Demonstration of Mechanically Exfoliated β-Ga2O3/GaN p-n Heterojunction”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  24. H. Chen, J. Zhou, T. H. Yang, H. Fu, J. Montes, X. Huang, K. Fu, J. Montes, C. Yang, and Y. Zhao, “Study of optical scattering loss induced by crystalline defects inside AlN waveguides using volume current method“, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  25. X. Huang, D. Li, H. Fu, H. Chen, K. Fu, C. Yang, T. H. Yang, J. Zhou, J. Montes, S. P. DenBaars, S. Nakamura, C. Z. Ning, and Y. Zhao, “High temperatures carrier dynamics of nonpolar and polar InGaN/GaN MQWs”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  26. J. Montes, H. Fu, T. H.  Yang, H. Chen, X. Huang, K. Fu, I. Baranowski, and Y. Zhao, “Effects of 3 MeV proton radiation on ultrawide bandgap aluminum nitride Schottky barrier diodes”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Poster Presentation.
  27. X. Huang, R. Fang, C. Yang, K. Fu, H. Fu, H. Chen, T. H. Yang, J. Zhou, J. Montes, M. Kozicki, H. Barnaby, B. Zhang, and Y. Zhao, “Steep-slope field-effect transistors with AlGaN/GaN HEMT and oxide based threshold switching device”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Poster Presentation.
  28. H. Liu, S. R. Alugubelli, P. Y. su, H. fu, K. Fu, Y. Zhao, and F. A. Ponce, “Nonuniform Mg doping in GaN epilayers grown on mesa structures,” The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  29. S. R. Alugubelli, H. Fu, K. Fu, H. Liu, Y. Zhao, and F. A. Ponce, “Dopant profiling in p-i-n GaN high power devices using secondary electrons”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Oral Presentation.
  30. S. R. Alugubelli, H. Fu, K. Fu, H. Liu, Y. Zhao, and F. A. Ponce, “Electronic band structure of etch-and-regrowth interface in p-i-n GaN films using electron holography”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Poster Presentation.
  31. A. Hatch, D. Messina, H. Fu, K. Fu, X. Wang, M. Hao, Y. Zhao, and R. J. Nemanich, “ALE of GaN (0001) for removal of etch-induced damage”, The 13th International Conference on Nitride Semiconductors 2019 (ICNS-13), Jul 2019, Bellevue, WA, Poster Presentation.
  32. H. Chen, J. Zhou, H. Fu, X. Huang, T. H. Yang, K. Fu, J. Montes, C. Yang, and Y. Zhao, “Supercontinuum generation from dispersion engineered AlN nanophotonics waveguide arrays”,  2019 CLEO, May 2019, San Jose, CA, Oral Presentation.
  33. H. Chen, J. Zhou, H. Fu, X. Huang, and Y. Zhao, “Study of Crystalline defect induced optical scattering loss inside AlN waveguides in UV-Visible spectral wavelengths “, 2019 CLEO, May 2019, San Jose, CA, Poster Presentation.
  34. K. Fu, H. Fu, H. Liu, S. R. Alugubelli, X. Huang, H. Chen, T. H. Yang, J. Montes, C. Yang, J. Zhaou, F. A. Ponce, and Y. Zhao, “1.2 kV regrown GaN vertical p-n power diodes with ultra low leakage using advanced materials engineering”, 2019 Compound Semiconductor Week (CSW 2019) and the 46th International Symposium on Compound Semiconductors (ISCS 2019), May 2019, Nara, Japan, Oral Presentation.
  35. K. Fu, H. Fu, X. Huang, T. H. Yang, H. Chen, J. Montes, C. Yang, J. Zhou, and Y. Zhao, “Threshold and resistive switching behaviors in epitaxially regrown GaN P-N diodes for high temperature applications,” 2019 Compound Semiconductor Week (CSW 2019) and the 46th International Symposium on Compound Semiconductors (ISCS 2019), May 2019, Nara, Japan, Poster Presentation.
  36. K. Fu, H. Fu, H. Liu, S. R. Alugubelli, T. H. Yang, X. Huang, H. Chen, I. Baranowski, J. Montes, F. A. Ponce, and Y. Zhao, “Investigation of GaN-on-GaN vertical p-n diode with regrown p-GaN by metalorganic chemical vapor deposition”,  2019 MRS Spring Meeting, Apr 2019, Phoenix, AZ, Oral Presentation.
  37. T. H. Yang, H.  Fu, H. Chen, X. Huang, J. Montes, I. Baranowski, K. Fu, and Y. Zhao, “The study on inhomogeneity of Ga2O3 Schottky barrier diodes by modified thermionic emission model”, 2019 MRS Spring Meeting, Apr 2019, Phoenix, AZ, Oral Presentation.
  38. H.  Fu, K. Fu, X. Huang, H. Chen, T. H. Yang, J. Montes, C. Yang, J. Zhou, and Y. Zhao, “Observation of threshold and resistive switching behaviors in epitaxially regrown GaN p-n diodes by MOCVD”, 2019 MRS Spring Meeting, Apr 2019, Phoenix, AZ, Poster Presentation (Late News).
  39. S. R. Alugubelli, H. Fu, K. Fu, H. Liu, Y. Zhao, and F. A. Ponce, “Dopant profiling using low-voltage SEM for GaN power electronics”, 2019 MRS Spring Meeting, Apr 2019, Phoenix, AZ, Poster Presentation.
  40. H. Liu, H. Fu, K. Fu, S. R. Alugubelli, P.-Y. Su, Y. Zhao, and F. A. Ponce, “Non-uniform Mg doping in GaN epilayers on mesa structures”, 2019 MRS Spring Meeting, Apr 2019, Phoenix, AZ, Poster Presentation.
  41. K. A. Hatch, K. Fu, H. Fu, J. Brown, D.C. Messina, X. Wang, M. Hao, Y. Zhao, and R.J. Nemanich, “Atomic layer etching for selective area doping of GaN”, 2018 MRS Fall Meeting, Nov 2018, Boston, MA, Poster Presentation.
  42. Y. Zhao, J. Montes, H. Fu, K. Fu, X. Huang, H. Chen, T. H. Yang, and I. Baranowski, “Progress on radiation effects in ultra-wide bandgap AlN Schottky barrier diodes”, 2018 IEEE Nuclear and Space Radiation Effects Conference (IEEE NSREC 2018), Jul 2018, Kona, HI, Poster Presentation (Late News). 
  43. H. Fu, H. Chen, X. Huang, I. Baranowski, J. Montes, T. H. Yang, and Y. Zhao, “Anisotropic electrical properties of vertical β-Ga2O3 Schottky barrier diodes on single-crystal substrates”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Oral Presentation. 
  44. H. Fu, X. Huang, H. Chen, I. Baranowski, J. Montes, T. H. Yang, and Y. Zhao, “1-kV-class AlN Schottky barrier diodes on sapphire substrates”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Oral Presentation. 
  45. X. Huang, H. Fu, H. Chen, I. Baranowski, J. Montes, T. H. Yang, K.Fu, B. P. Gunning, D. Koleske, and Y. Zhao, “Thermal reliability analysis of InGaN MQW solar cells”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Oral Presentation. 
  46. X. Huang, H. Fu, H. Chen, I. Baranowski, J. Montes, T. H. Yang, K.Fu, B. P. Gunning, D. Koleske, and Y. Zhao, “Band engineering of InGaN/GaN multiple-quantum-well (MQW) solar cells”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Oral Presentation. 
  47. H. Fu, R. Hao, B. Zhang, and Y. Zhao, “Normally-off p-GaN/AlGaN/GaN HEMTs by hydrogen plasma treatment”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Oral Presentation. 
  48. J. Montes, H. Fu, T. H. Yang, H. Chen, X. Huang, I. Baranowski, K.Fu, and Y. Zhao, “Gamma-ray and proton radiation effects in AlN Schottky barrier diodes”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Poster Presentation. 
  49. I. Baranowski, H. Chen, H. Fu, J. Montes, K.Fu, T. H. Yang, , X. Huang, and Y. Zhao, “Thermal performance of silicon dioxide conduction blocking layers in GaN VHEMT devices ”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Poster Presentation. 
  50. T. H. Yang, H. Fu, X. Huang, H. Chen, J. Montes, I. Baranowski, K. Fu, and Y. Zhao, “Temperature-dependentelectrical properties of beta-Ga2O3 Schottky barrier diodes on highly doped single-crystal substrates and their reverse current leakage mechanisms”, 2018 Compound Semiconductor Week (CSW 2018) and the 45th International Symposium on Compound Semiconductors (ISCS 2018), May 2018, Boston, MA, Poster Presentation. 
  51. H. Fu, H. Chen, X. Huang, I. Baranowski, J. Montes, T. H. Yang, and Y. Zhao, “Effect of crystalline anisotropy on (-201) and (010) β-Ga2O3 Schottky barrier diodes fabricated on single-crystal substrates”, 2018 MRS Spring Meeting, Apr 2018, Phoenix, AZ, Oral Presentation. 
  52. H. Chen, H. Fu, X. Huang, and Y. Zhao, “Loss mechanism study and fabrication of III-N photonic waveguide for integrated photonics applications at visible spectral wavelength”, 2018 MRS Spring Meeting, Apr 2018, Phoenix, AZ, Oral Presentations.
  53. X. Huang, H. Fu, H. Chen, I. Baranowski, J. Montes, T. H. Yang, B. P. Gunning, D. Koleske, and Y. Zhao, “Thermal reliability analysis of InGaN solar cells”, 2018 MRS Spring Meeting, Apr 2018, Phoenix, AZ, Oral Presentations.
  54. J. Montes, H. Fu, H. Chen, X. Huang, T. H. Yang, I. Baranowski, and Y. Zhao, “Radiation effects in ultra-wide bandgap AlN Schottky barrier diodes”, 2018 MRS Spring Meeting, Apr 2018, Phoenix, AZ, Oral Presentations.
  55. I. Baranowski, H. Fu, H. Chen, X. Huang, T. H. Yang, J. Montes, and Y. Zhao, “Thermal TCAD simulations of silicon dioxide conduction blocking layers in GaN vertical high electron mobility transistors”, 2018 MRS Spring Meeting, Apr 2018, Phoenix, AZ, Poster Presentations.
  56. H. Chen, X. Huang, H. Fu, Z. Lu, J. Montes, and Y. Zhao, “Characterizations of Kerr refractive index and nonlinear absorption on GaN crystals in polar, nonpolar and semipolar orientations”, The 59th Electronic Materials Conference (EMC 2017), Jun 2017, South Bend, IN, Oral Presentation.
  57. Huang, H. Fu, H. Chen, Z. Lu, J. Montes, M. Iza, S. P. DenBaars, S. Nakamura, and Y. Zhao, “Outstanding high temperature performance of nonpolar and semipolar InGaN solar cells”, The 59th Electronic Materials Conference (EMC 2017), Jun 2017, South Bend, IN, Oral Presentation.
  58. H. Fu, X. Huang, H. Chen, Z. Lu, X. Zhang, and  Y. Zhao, “Analysis of reversed breakdown and leakage mechanisms of AlN Schottky diodes operating at elevated temperature”, 2017 MRS Spring Meeting, Apr 2017, Phoenix, AZ, Oral Presentations.
  59. X. Huang, H. Fu, H. Chen, Z. Lu, X. Zhang, M. Iza, S. DenBaars, S. Nakamura, and  Y. Zhao, “Demonstration of Nonpolar and semipolar InGaN/GaN multi-quantum well (MQW) solar cells”, 2017 MRS Spring Meeting, Apr 2017, Phoenix, AZ, Oral Presentations.
  60. H. Fu, X. Huang, H. Chen, Z. Lu, and Y. Zhao, “On the reverse breakdown and leakage mechanisms of AlN Schottky diodes at high temperature”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Poster Presentation (Late News).
  61. X. Huang, H. Fu, H. Chen, Z. Lu, D. Ding, and Y. Zhao, “Farbication and characterization of nonpolar and semipolar InGaN/GaN multi-quantum well (MQW) solar cells”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Oral Presentation (Late News).
  62. X. Huang, H. Fu, H. Chen, Z. Lu, D. Ding, and Y. Zhao, “Theoretical study on efficiency limits and loss analysis for single-junction InGaN solar cells using a semi-analytical model”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Oral Presentation.
  63. Z. Lu, P. Tian, H. Fu, X. Huang, H. Chen, X. Liu, R. Liu, and Y. Zhao, “The effect of reflection on visible light communication system using a Gallium Nitride uLED and IEEE 802.11ac”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Poster Presentation.
  64. H. Fu, Z. Lu, X huang, H. Chen, and Y. Zhao, “Crystal orientation dependent intersubband transition in semipolar AlGaN/GaN quantum well for optoelectronic applications”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Oral Presentation.
  65. H. Chen, H. Fu, X. Huang, Z. Lu, and Y. Zhao, “Polarization-dependent emission properties of InGaN light-emitting diodes modified by metallic grating”, 2016 International Workshop on Nitride Semiconductors (IWN 2016), Oct 2016, Orlando, FL, Poster Presentation.
  66. X. Huang, H. Fu, H. Chen, Z. Lv, D. Ding, and Y. Zhao, “Analysis of loss mechanisms in single-junction InGaN solar cells using a semi-analytical model”, The 58th TMS Electronic Materials Conference (EMC 2016), Jun 2016, Newark, DE, Oral Presentation.
  67. H. Fu, Z. Lu, X. Huang, H. Chen, and Y. Zhao, “Terahertz Intersubband Transition in Semipolar AlGaN/GaN Quantum Wells for Optoelectronic Applications”, The 58th Electronic Materials Conference (EMC 2016), Jun 2016, Newark, DE, Oral Presentation.
  68. H. Chen, H. Fu, Z. Lu, X. Huang, and Y. Zhao, “Optical Properties of Highly Polarized InGaN Light-Emiting Diodes Coated with Silver Grating”, The 58th Electronic Materials Conference (EMC 2016), Jun 2016, Newark, DE, Oral Presentation.
  69. X. Huang, H. Fu, H. Chen, Z. Lv, D. Ding, and Y. Zhao,  “Device Simulation and Loss Analysis for Single-Junction InGaN Solar Cells Using a Semi-Analytical Model” ,The 43rd IEEE Photovoltaic Specialists Conference (PVSC 2016), Jun 2016, Portland, OR, Poster Presentation.
  70. Z. Lu, H. Wang, S. Naqvi, Y. Zhao, H. Song, and J. M. B. Christen, “A Point of Care Electrochemical Impedance Spectroscopy Device”, The 28th IEEE  International System-on-Chip Conference (SOCC 2015), Sep 2015, Beijing, China, Oral Presentation.
  71. H. Fu, Z. Lu, and Y. Zhao, “Weak phase-space willing effect on the modeling of low-droop semipolar InGaN light emitting diodes”, The 11th International Conference on Nitride Semiconductors (ICNS 2015), Aug 2015, Beijing, China, Oral Presentation.
  72. H. Fu, Z. Lu, and Y. Zhao, “The modeling of low-droop semipolar InGaN light emitting diodes with weak phase-space filling effect”, 2015 Compound Semiconductor Week (CSW 2015) and the 42nd International Symposium on Compound Semiconductors (ISCS 2015), Jun 2015, Santa Barbara, CA, Oral Presentation.
  73. Z. Lu, H. Fu, H. Song, and Y. Zhao, “A CMOS sun tracker for an application of CPV”, 2015 Compound Semiconductor Week (CSW 2015) and the 42nd International Symposium on Compound Semiconductors (ISCS 2015), Jun 2015, Santa Barbara, CA, Poster Presentation.
  74. S. Marcinkevicius, K. Gelzinyte, R. Ivanov, Y. Zhao, S. Nakamura, S. P.DenBaars, and J. S. Speck, “Optical properties of semipolar (20-21) plane InGaN quantum wells studied on the nanoscale”, 2015 Compound Semiconductor Week (CSW 2015) and the 42nd International Symposium on Compound Semiconductors (ISCS 2015), Jun 2015, Santa Barbara, CA, Poster Presentation.
  75. H. Fu, Z. Lu, and Y. Zhao, “The modeling of low-droop semipolar InGaN light emitting diodes with weak phase-space filling effect”, The 57th TMS Electronic Materials Conference (EMC 2015), Jun 2015,Columbus, OH, Oral Presentation.
  76. S. Marcinkevicius, R. Ivanov, Y. Zhao, S. Nakamura, S. P.DenBaars, and J. S. Speck, “Spatial variations of optical properties of semipolar InGaN quantum wells”, Photonics West 2015, Feb 2015, San Francisco, CA, Oral Presentation.
  77. S. Marcinkevicius, Y. Zhao, S. Nakamura, S. P.DenBaars, and J. S. Speck, “Optical properties of semipolar (20-2-1) InGaN/GaN quantum wells”, 2014 International Workshop on Nitride Semiconductors (IWN 2014), Aug 2014, Wroclaw, Poland, Oral Presentation.
  78. S. Marcinkevicius, Y. Zhao, K. Kelchner, S. Nakamura, S. P.DenBaars, and J. S. Speck, “Near‐field optical spectroscopy of band potential variations innonpolar and semipolar InGaN quantum wells”, The 41st International Symposium on Compound Semiconductors (ISCS 2014), May 2014, Montpellier, France, Oral Presentation.
  79. Y. Zhao, F. Wu, S. Nakamura, and J. S. Speck, “Structure characterization of atomic scale nanofacet in semipolar (20-2-1) and (20-21) InGaN single quantum well”, The 56th TMS Electronic Materials Conference (EMC 2014), Jun 2014, Santa Barbara, CA, Oral Presentation.
  80. D. L. Becerra,Y. Zhao, S. H. Oh, C. D. Pynn, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Growth and characterization of semipolar (30-3-1) InGaN light-emitting diodes with high power and low efficiency droop”, The 56th TMS Electronic Materials Conference (EMC 2014), Jun 2014, Santa Barbara, CA, Oral Presentation.
  81. Y. Zhao, F. Wu, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Growth and characterization of semipolar (20-2-1) green InGaN light-emitting diodes”, The 55th TMS Electronic Materials Conference (EMC 2013), Jun 2013, University of Notre Dame, IN, Oral Presentation.
  82. Y. Zhao, C. Y. Huang, C. C. Pan, S. Tanaka, Y. Kawaguchi, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Semipolar (20-2-1) InGaN light-emitting diodes and laser diodes”, 2012 International Workshop on Nitride Semiconductors (IWN 2012), Oct2012, Sapporo, Japan, Oral Presentation.
  83. C. Y. Huang, Y. Zhao, Q. Yan, Y. Kawaguchi, Y. R. Wu, D. Feezell, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Carrier transports in semipolar multiple-quantum-wells light-emitting diodes”, 2012 International Workshop on Nitride Semiconductors (IWN 2012), Oct 2012, Sapporo, Japan, Oral Presentation.
  84. C. Y. Huang, M. T. Hardy, Y. Zhao, Q. Yan, A. Pourhashemi, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Semipolar (20-2-1) blue to aquamarine laser diodes with minimal wavelength blueshift”, 2012 International Workshop on Nitride Semiconductors (IWN 2012), Oct 2012, Sapporo, Japan, Oral Presentation. (Nominated for best paper award.)
  85. C. Y. Huang, Y. Zhao, F. Wu, Y. Kawaguchi, D. Feezell, S. P. DenBaars, J. S. Speck, and S. Nakamura, “Growth characteristics of InGaN/GaN quantum wells on semipolar (20-21) and (20-2-1) planes”, 2012 International Workshop on Nitride Semiconductors (IWN 2012), Oct 2012, Sapporo, Japan, Post Presentation.
  86. C. C. Pan, S. Tanaka, F. Wu, Y. Zhao, J. S. Speck, S. Nakamura, S. P. DenBaars, and D. Feezell, “High-power, low-efficiency-droop semipolar (20-2-1) single-quantum-well blue light-emitting diodes”, 2012 International Workshop on Nitride Semiconductors (IWN 2012), Oct 2012, Sapporo, Japan, Poster Presentation.
  87. Y. Zhao, Q. Yan, D. Feezell, K. Fujito, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Optical polarization characterization of semipolar (30-3-1) and (30-31) blue-green InGaN/GaN light-emitting diodes”, The 39th International Symposium on Compound Semiconductors (ISCS 2012), Aug 2012, Santa Barbara, CA, Oral Presentation.
  88. Y. Zhao, C. Y. Huang, S. Tanaka, C. C. Pan, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Semipolar (20-2-1) blue and green InGaN light-emitting diodes”, 2012 Conference on Lasers and Electro-Optics (CLEO 2012), May 2012, San Francisco, CA, Oral Presentation. (Nominated for best paper award & Highlighted as notable research breakthrough by American Institute of Physics and Optical Society of America & Reported by Science Magazine.)
  89. C. Y. Huang, Y. Zhao, M. T. Hardy, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Semipolar (20-2-1) laser diodes (λ=505 nm) with wavelength stable InGaN/GaN quantum wells”, 2012 Conference on Lasers and Electro-Optics (CLEO 2012), May 2012, San Francisco, CA, Oral Presentation.
  90. D. Feezell, Y. Zhao, C. C. Pan, S. Tanaka, C. Y. Huang, F. Wu, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Low droop and high efficiency semipolar (20-2-1) light-emitting diodes (LEDs)”, SPIE Photonics West 2012, Jan 2012, San Francisco, CA, Oral Presentation.
  91. Y. Zhao, S. Tanaka, C. C. Pan, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “High performance semipolar (20-2-1) InGaN/GaN light-emitting diodes”, 2011 Material Research Society Fall Meeting (MRS Fall 2011), Nov 2011, Boston, MA, Oral Presentation.
  92. Y. Zhao, S. Tanaka, R. B. Chung, C. C. Pan, K. Fujito, D. Feezell, J. S. Speck, S. P. DenBaars, and S. Nakamura, “Highly polarized spontaneous emission from semipolar (20-2-1) InGaN/GaN light-emitting diodes”, The 53rd TMS Electronic Materials Conference (EMC 2011), Jun 2011, Santa Barbara, CA, Oral Presentation.
  93. Y. Zhao, J. Sonoda, I. Koslow, C. C. Pan, S. Yamamoto, K. Fujito, H. Ohto, J. S. Ha, S. P. DenBaars, and S. Nakamura, “High internal and extraction efficiency in semipolar GaN-based LEDs”, 2010 International Workshop on Nitride Semiconductor (IWN 2010), Sep 2010, Tampa, FL, Oral Presentation.
  94. I. Koslow, J. Richardson, J. Sonoda, C. C. Pan, Y. Zhao, J. S. Ha, F. Lange, S. Nakamura, S. P. DenBaars, “Light-emitting diodes with ZnO current spreading layers grown by aqueous solution on various crystallographic planes of GaN”, 2010 International Workshop on Nitride Semiconductor (IWN 2010), Sep 2010, Tampa, FL, Poster Presentation.