High-Performance Self-Driven Single Gan-Based P-I-N Homojunction One-Dimensional Microwire Ultraviolet Photodetector

A B S T R A C TWith the increasing global concern about energy consumption, self-driven photodetectors that can operate without an external power supply are particularly attractive. In this paper, we present a high performance self-driven single GaN-based p-i-n homojunction one-dimensional microwire ultraviolet photodetector (UV PD) with vertical structure. High-quality trapezoidal GaN-based p-i-n homojunction microwires were selectively heteroepitaxially grown on a patterned Si(100) substrate by Metal Organic Chemical Vapor Deposition (MOCVD). The upper and lower electrodes were separated by simple spin coating and photolithography. The single GaN-based p-i-n homojunction microwire UV PD exhibits excellent self-driven characteristics under 325 nm light illumination, including a low dark current (10 pA), a fast response speed (T r = 1.12 ms / T d = 2.8 ms), and a excellent detectivity (2.81×10 12 jones). In addition, The UV PD has high responsivity (2.16 A/W) at 0 V. The high performance of the UV PD is mainly due to the wider built-in electric field formed in the p-i-n junction and vertical conductive structure with reduced dimensionality. This study not only provides a simple and feasible method to fabricate one-dimensional vertical structured microwire UV PDs, but also provides a basis for the subsequent fabrication of UV PDs with high-performance self-driven homojunctions