High-performance self-powered deep ultraviolet photodetector based on MoS2/GaN p–n heterojunction

Abstract

High-performances deep-ultraviolet (DUV) photodetectors (PDs) are highly desired due to their great importance in numerous fields. In this study, self-powered MoS₂/GaN p–n heterojunction PDs were constructed, which exhibited high sensitivity to DUV light illumination and pronounced photovoltaic behaviours. Photoresponse analysis revealed a high responsivity of 187 mA W⁻¹, a high specific detectivity of 2.34 × 10¹³ Jones, a high linear dynamic range of 97.3 dB and fast response speeds of 46.4/114.1 μs (5 kHz) under a DUV light of 265 nm at zero bias voltage without an external power supply. Moreover, the MoS₂/GaN p–n heterojunction PD could operate with excellent stability and repeatability in a wide frequency range over 10 kHz. The high performance could be attributed to the enhancment by the built-in electric field in the heterojunction. It is expected that such high-performance self-powered DUV PDs will have great potential applications in the future.