High-Performance Ga<sub>2</sub>O<sub>3</sub> Solar-Blind Photodetector Based on Thermal Oxidized Ga Buffer-Layer
Haofei Huang, Lulu Wang, Lulu Wang, Haichuan Zhou, Hengzhi Xing, Lujun Wang, Lujun Wang, Wei Zhang, Ke Tang, Jian Huang, Linjun Wang, Linjun Wang
Abstract
High-performance Ga 2 O 3 solar-blind photodetectors are critical for applications due to their selective solar-blind ultraviolet sensitivity. The quality of the Ga 2 O 3 film has a significant impact on the performance of photodetectors. This study presents an innovative approach to enhancing the quality of Ga 2 O 3 films through the introduction of a naturally graded buffer layer, which is formed by the oxidation of a metallic Ga film and significantly improves interface stability by accommodating lattice mismatches and reducing defects. The structural and compositional characteristics of Ga 2 O 3 films were comprehensively analyzed using UV–vis (ultraviolet–visible) spectroscopy, AFM (Atomic Force Microscope), PL (Photoluminescence Spectroscopy), TEM (Transmission Electron Microscope), and XPS (X-ray Photoelectron Spectroscopy). The photodetectors fabricated from these films demonstrate responsivity of 99.8 mA/W and a solar-blind UV/UV ratio of 1.17 × 10 3, with significant improvement compared to direct deposited films. This research highlights the potential of natural buffering layers to advance the performance of Ga 2 O 3 -based solar-blind UV detectors.