Vertical Solar-Blind Deep-Ultraviolet Schottky Photodetectors Based on β-Ga2O3Substrates

作者：Takayoshi Oshima, Takeya Okuno, Naoki Arai, Norihito Suzuki, Shigeo Ohira, Shizυo Fujita · 发表于：Applied Physics Express · 年份：2008 · DOI：10.1143/apex.1.011202 · 被引用次数：404 · 研究领域：Ga2O3 and related materials、ZnO doping and properties、Gas Sensing Nanomaterials and Sensors

A vertical-type Schottky photodetector based on a (100)-oriented β-Ga 2 O 3 substrate has been fabricated with simple processes of thermal annealing and vacuum evaporation. The photodetector exhibited a rectification ratio higher than 10 6 at ±3 V, and showed deep-ultraviolet-light detection at reverse bias. The spectral response showed solar-blind sensitivity with high photoresponsivities of 2.6–8.7 A/W at wavelengths of 200–260 nm. These values were 35–150 times higher than those derived assuming the internal quantum efficiency to be unity. This fact is attributed to the carrier multiplication occurring in the highly resistive surface region that is subject to a high internal electric field of about 1.0 MV/cm at the reverse bias of 10 V.