Directional Carrier Transport in Micrometer-Thick Gallium Oxide Films for High-Performance Deep-Ultraviolet Photodetection

• DOI: 10.1021/acsami.3c00124
• Publication Date: 2023-02-16T14:12:50Z
• Authors: Wenrui Zhang; Wei Wang; Jinfu Zhang; Tan Zhang; Li Chen; Liu Wang; Yu Zhang; Yanwei Cao; Li Ji; Jichun Ye
• Keywords: Photodetection; Ultraviolet; Gallium Oxide; Micrometer

Incorporating emerging ultrawide bandgap semiconductors with a metal-semiconductor-metal (MSM) architecture is highly desired for deep-ultraviolet (DUV) photodetection. However, synthesis-induced defects in complicate the rational design of MSM DUV photodetectors due to their dual role as carrier donors and trap centers, leading commonly observed trade-off between responsivity response time. Here, we demonstrate simultaneous improvement these two parameters {\epsilon}-Ga2O3 by establishing low-defect diffusion barrier directional transport. Specifically, using micrometer thickness far exceeding its effective light absorption depth, photodetector achieves over 18-fold enhancement reduction time, which exhibits state-of-the-art photo-to-dark current ratio near 10^8, superior >1300 A/W, an ultrahigh detectivity >10^16 Jones decay time 123 ms. Combined depth-profile spectroscopic microscopic analysis reveals existence broad defective region lattice-mismatched interface followed more defect-free dark region, while latter one serves assist frontward transport substantially enhancing performance. This work critical semiconductor defect profile tuning fabricating high-performance photodetectors.