AlGaN solar-blind avalanche photodiodes with high multiplication gain

Abstract

We report the fabrication and characterization of the solar-blind AlGaN avalanche photodiodes grown by metal-organic chemical vapor deposition on c-plane sapphire substrate. The fabricated devices with 100 μm diameter active area exhibit a peak responsivity of 79.8 mA/W at 270 nm and zero bias, corresponding to an external quantum efficiency of 37%. Multiplication gains as high as more than 2500 were obtained in these devices.