Thermally stable photosensing using poly(methyl methacrylate)-coated MoS2 phototransistor for improved imaging reliability

Abstract

In this paper, we report thermally stable photosensing using MoS2 phototransistor with a poly(methyl methacrylate) (PMMA) coating. The increase in the OFF current of the PMMA-coated MoS2 phototransistor degraded to less than 87.72% of that of the pristine MoS2 phototransistor under harsh temperature conditions (250C). PMMA coating on the pristine MoS2 phototransistor improved the photosensitivity and drain current stability as a function of time by 315.71% at 250C and 91.26% under intense negative bias temperature illumination stress (NBTIS) test (Vgs = −30 V, Vds = 10 V, λex = 638 nm, Pinc = 1.0 mW, and T = 250C), respectively. This simple and useful method provides valuable insight for improving the reliability of photodetectors and image sensor systems under harsh temperature.