Efficient Suppression of Persistent Photoconductivity in β-Ga 2 O 3 -Based Photodetectors with Square Nanopore Arrays.

In this work, square nanopore arrays were developed on the surface of β-Ga 2 O 3 microflakes using focused ion beam (FIB) etching, and solar-blind photodetectors (PDs) were fabricated based on the β-Ga 2 O 3 microflakes with square nanopore arrays. The β-Ga 2 O 3 microflake-based device was transformed from a gate voltage depletion mode to an oxygen depletion mode by FIB etching. The developed device exhibited excellent solar-blind PD performance with extremely high responsivity (1.8 × 10 5 at 10 V), detectivity (3.4 × 10 18 Jones at 10 V), and light-to-dark ratio (9.3 × 10 8 at 5 V) as well as good repeatability and excellent stability. The intrinsic mechanism responsible for this performance was then systematically discussed. This work opens up a new avenue for the fabrication of high-performance β-Ga 2 O 3 -based low-dimensional PDs with high reproducibility by employing the FIB etching process.