A high responsivity, high detectivity, and high response speed MSM UVB photodetector based on SnO2 microwires

Abstract

We report a high performance UVB photodetector with a metal–semiconductor–metal device structure based on high crystal quality SnO₂ microwires prepared by chemical vapor deposition. Under 10 V bias, a low dark current of 3.69 × 10⁻⁹ A and a high light-to-dark current ratio of 1630 were achieved. The device showed a high responsivity of about 1353.0 A·W⁻¹ under 322 nm light illumination. The detectivity of the device is as high as 5.4 × 10¹⁴ Jones, which ensures the detection of weak signals in the UVB spectral region. Due to the small amount of deep-level defect-induced carrier recombination, the light response rise time and fall time are shorter than 0.08 s.