Comprehensive analysis of optoelectronic performance of ultraviolet phototransistors based on AlGaN/GaN heterostructure

Optoelectronic performance of ultraviolet phototransistors (UVPTs) based on AlGaN/GaN high-electron-mobility transistor (HEMT) configuration is comprehensively studied under different illumination wavelengths, light power densities, gate biases, and drain voltages. A special photoresponse mechanism combining photovoltaic effect and photoconductive effect is proposed to explain the variation of detection performance with the optical and electrical conditions. By comparing the photoreponse characteristics under typical illumination wavelengths of 310 and 360 nm, the optoelectronic properties of the HEMT-based UVPTs are deeply revealed and summarized. This work can provide suggestions and guidelines for designing of AlGaN/GaN-based UVPTs in III-V integrated photonic systems.