High-Performance Photodetectors Using a 2D MoS₂/3D-AlN Structure

Abstract

Two-dimensional material MoS2 has excellent optical and electrical characteristics and a controllable energy band structure, leading to a high potential value for designing photodetectors. In this work, a kind of van der Waals heterostructure composed of AlN and a MoS2 photodetector was fabricated. The optical properties of MoS2 can be improved by the polarization effect of AlN. On this basis, with a 3 nm thick Al2O3 layer deposited on the MoS2 layer, the strain effects were also investigated to improve the performance of the detector. The result showed that under an illumination of 365 nm wavelength, the stress liner device showed excellent performance relative to the control device and the photocurrent and responsivity were improved by more than five times. Our work provides guidance for developing heterostructure photoelectric devices and also proves the role of strain engineering in improving the performance of photodetectors.