Optical-enhanced, self-powered UV photodetectors based on VO2/SiC heterojunction

Abstract

The development of ultraviolet (UV) heterojunction photodetectors plays a critical role in a wide range of applications, including environmental monitoring, biomedical imaging, and secure communications. In this study, we present self-powered solar-blind UV photodetectors based on a vanadium dioxide (VO2)/silicon carbide (SiC) heterojunction. The integration of the narrow-bandgap VO2 film with the wide-bandgap SiC creates a Z-type heterojunction, which significantly enhances photocurrent due to the built-in electric field at the interface. Furthermore, a notable increase in photocurrent is achieved by the deposition of gold nanoparticles on the device's surface. This modification enhances the local electric field via the plasmonic effects, thereby further improving photocurrent. The synergistic effect of the plasmonic field enhancement effect and the built-in electric field of the heterojunction enhances the generation, separation, and transport efficiency of photogenerated carriers, ultimately resulting in a superior photocurrent response. The self-powered UV heterojunction photodetector offers a promising strategy for the advancement of SiC-based optoelectronic devices.