Facile construction of p-Si/n-SnO2 junction towards high performance self-powered UV photodetector

Abstract Recently, self-powered ultraviolet photodetectors (UV PDs) based on SnO 2 have gained increasing interest due to its feature of working continuously without the need for external power sources. Nevertheless, the production of the majority of these existing UV PDs necessitates additional manufacturing stages or intricate processes. In this work, we present a facile, cost-effective approach for the fabrication of a self-powered UV PD based on p-Si/n-SnO 2 junction. The self-powered device was achieved simply by integrating a p-Si substrate with a n-type SnO 2 microbelt, which was synthesized via the chemical vapor deposition (CVD) method. The high-quality feature, coupled with the belt-like shape of the SnO 2 microbelt enables the favorable contact between the n-type SnO 2 and p-type silicon. The built-in electric field created at the interface endows the self-powered performance of the device. The p-Si/n-SnO 2 junction photodetector demonstrated a high responsivity (0.12 mA/W), high light/dark current ratio (>10 3 ), and rapid response speed at zero bias. This method offers a practical way to develop cost-effective and high-performance self-powered UV PDs.