Ultrathin Ga<sub>2</sub>O<sub>3</sub> Photodetector with Fast Response and Trajectory Tracking Capability Fabricated by Liquid Metal Oxidation.

Zhong, Weiheng; Liu, Yuqing; Huang, Hong; Sun, Zhaojie; Xin, Wei; Liu, Weizhen; Zhao, Xiaolong; Long, Shibing et al. · Nano Lett · 2024

basic_science · Level V

Where this comes from

Abstract

Low-dimensional Ga<sub>2</sub>O<sub>3</sub> demonstrates a unique ultraviolet photoresponse and could be used in various electronic and optical systems. However, the low-dimensional Ga<sub>2</sub>O<sub>3</sub> photodetector is faced with the challenges of a complex preparation process and poor device performance. In this work, ultrathin Ga<sub>2</sub>O<sub>3</sub> layers with ∼7 nm thickness are prepared on quartz rods by UV exposure to liquid gallium. Benefiting from low-density oxygen vacancy defects cured by UV exposure, the low-dimensional Ga<sub>2</sub>O<sub>3</sub> photodetector exhibits a high response speed (rise: 64.7 μs; fall: 51.4 μs) and an exceptional linear dynamic range of 120 dB. Furthermore, the photodetector array based on these ultrathin Ga<sub>2</sub>O<sub>3</sub> shows an effective trajectory tracking capability by monitoring UV source motion. This work develops a simple preparation method to construct a low-dimensional UV photodetector array with fast response and useful trajectory tracking capability, exhibiting the significance of ultrathin Ga<sub>2</sub>O<sub>3</sub> in UV optoelectronics.