1877
Transparent Ga2O3 Photodetectors for Harsh Optoelectronics

Tuesday, 7 October 2014: 11:20
Expo Center, 1st Floor, Universal 10 (Moon Palace Resort)
T. C. Wei, D. S. Tsai (Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan), P. Ravadgar (the Department of Photonics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan), J. J. Ke (Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan, ROC), M. L. Tsai (the Department of Electrical Engineering, and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan), D. H. Lien (Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan, ROC), C. Y. Huang (the Department of Materials Science and Engineering, National Chung Hsing University), R. H. Horng (the Graduate Institute of Precision Engineering, National Chung Hsing University, Taichung, Taiwan), and J. H. He (Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, Taiwan)
We fabricate fully transparent solar-blind DUV PD devices employing β-Ga2O3 as an active layer and indium zinc oxide (IZO) as the transparent electrodes, exhibiting the average transmittance up to 80% from visible to near IR wavelength region without image blurring. The β-Ga2O3 MSM PDs for the use in harsh environments show a very low dark current (~1 nA), no sign of breakdown even at a bias higher than 200 V, excellent thermal stability, and intrinsic solar blindness. The dark current of β-Ga2O3 MSM PDs under significantly different oxygen concentration in the ambiences is similar, indicating that the high inertness to surface effect due to superior crystallinity nature of β-Ga2O3. The working temperature is up to 700 K and the responsivity is 0.32 mA/W at 10 V bias under 185-nm illumination. β-Ga2O3 PDs can be fully recovered after 700-K operation, showing excellent thermal reliability and robustness. The intriguing optoelectronic and electrical properties of β-Ga2O3 promise a new generation of stable, solar-blind DUV PDs for the extremely harsh electronic applications, such as sensing, imaging, and intrachip optical interconnects in high-temperature environments.