Fast Speed Ga2O3 Solar-blind Schottky Photodiodes with Large Sensitive Area
Yang Xu, Xuanhu Chen, Yanfang Zhang, Fangfang Ren, Shulin Gu, Jiandong Ye
Abstract
We reported on a fast-speed and self-powered β-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> vertical Schottky solar-blind photodiodes of 7 mm × 7 mm detecting area. Operated at zero bias, this photovoltaic diode exhibits a peak responsivity of 9.78 A/W at 212 nm with its corresponding specific detectivity of 3.29 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">14</sup> Jones. An UVC-to-UVA rejection ratio over 104 is also achieved that is mainly limited by the internal photoemission of hot electrons from metal injecting into Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> . In particular, the diode exhibits a recorded shortest response time of <; 5 μs, which is the first report of RC-time-limited performance for Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> photodetectors reported to date. Along with the large sensitive area, high detectivity and fast response speed allows them suitable for the real time response to objectives with high speed and weak flux of solar-blind spectral signal or high-energy radiations.