Temperature-Dependent Electrical Transport and Optoelectronic Properties of SnS₂/p-Si Heterojunction

Abstract

Heterojunctions based on two-dimensional (2D)/three-dimensional (3D) semiconductors have become an integral component of next-generation optoelectronic devices. Here, we report the photodetection and electrical transport properties of SnS2/p-Si heterojunction. The device shows a high spectral responsivity of 3.04 A/W (at an applied reverse bias of 1 V) at a wavelength of 560 nm, with response/recovery times of 32.7/9.8 μs. The nonlinear dependence of photocurrent on the incident light power density observed in the present investigation is attributed to the presence of interfacial defects, which corroborates the anomalies observed in the electrical transport analysis of the device in the temperature range of 85–300 K. The current–voltage characteristics suggest a nonideal behavior, and this deviation is due to the surface or interfacial defects and an inhomogeneity of barrier heights (BHs) at the heterointerface. These barrier inhomogeneities have been explained using a double Gaussian distribution of BHs, based on the thermionic emission theory. The mean BHs are estimated to be 0.65 and 1.35 eV in two different temperature regions, that is, 85–140 and 180–300 K, respectively. The present analysis would be beneficial for fabrication of high-quality and low-cost photonic devices and facilitate deeper understanding of the electrical properties of such 2D/3D heterojunctions.