Realization of in-Plane GaN Microwire Array Based Ultraviolet Photodetector with High Responsivity on a Si(100) Substrate

Recent years have witnessed one-dimensional materials and structures delivering their great superiority in various (opto-)electronic devices. However, highly controllable morphology, distribution, and structure of one-dimensional materials are hard to synthesize, which hindered their progress and applications. In this paper, ultraviolet photodetectors were fabricated on planar, parallel, and uniform GaN microwire arrays synthesized via catalyst-free heteroepitaxy by metal–organic chemical vapor deposition. Under illumination of 325 nm incident light at a bias of 5.0 V, the Schottky-type ultraviolet photodetector exhibits a strong responsivity of 1.17 × 10 5 A/W, as well as a high quantum efficiency of 4.47 × 10 5, which are much better than the most reported GaN nano/microwire-based ultraviolet photodetector, and it is a thin film based detector. Furthermore, the time-dependent photoresponse manifests their excellent repeatability and fast response (36.3 ms for rise time and 75.2 ms for decay time). Our work provides a high repeatability and efficient method to fabricate a high-performance GaN microwire array ultraviolet photodetector for future photoelectronic applications, even on-chip optoelectronic integrated systems.