Solar-Blind Photodetector Based on Single Crystal Ga2O3 Film Prepared by a Unique Ion-Cutting Process

A solar-blind photodetector based on single crystal beta-Ga2O3 thin film transferred on a SiC substrate with an Al2O3 buffer layer was prepared by a unique ion-cutting process. The structure and micromorphology of the transferred single crystal Ga2O3 film was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy, respectively. Then, a photodetector with a metal-semiconductor-metal (MSM) structure was fabricated. The photodetector performance of the MSM photodetector cells based on the ion-cutting single crystal Ga2O3 thin film reveals an excellent solar-blind photodetector performance such as high spectra selectivity, extremely low dark current (28.7 pA at 10 V), high photocurrent (27.4 nA at 10 V), high sensitivity to 254 nm UV light with a photocurrent-to-dark current ratio of 953, relatively fast response time, and excellent stability. Furthermore, the inner mechanism was systematically discussed. This work not only paves a way to fabricate high-performance photodetectors based on single crystal semiconductor films but also opens up the opportunities of Ga2O3 single crystal film for a variety of photonic and electronic applications in optical positioning, tracking, imaging, and communications.

Automated summary

A solar-blind photodetector based on single crystal beta-Ga2O3 thin film transferred on a SiC substrate with an Al2O3 buffer layer was prepared using a unique ion-cutting process. The photodetector exhibited excellent performance with high spectra selectivity, extremely low dark current, high photocurrent, high sensitivity to 254 nm UV light, fast response time, and stability, paving the way for high-performance photodetectors based on single crystal semiconductor films.