Photoelectrical performance of Cu₂MnSnS₄/p-Si photosensor for solar energy applications

The Cu₂MnSnS₄ (CMTS) film was prepared using the hydrothermal technique. The CMTS thin film was analyzed by the techniques of Ultraviolet–Visible (UV–Vis) spectroscopy, energy-dispersive X-ray (EDX or EDS), and scanning electron microscopy (SEM). To fabricate Al/Cu₂MnSnS₄ (CMTS)/p-Si/Al diode, the CMTS film was covered on p-Si wafer by a sol–gel spin-coating technique and the metallic contacts were prepared on film with pure aluminum. The current–voltage (I–V) properties of Al/Cu₂MnSnS₄ (CMTS)/p-Si/Al device were analyzed under dark and distinct illumination intensities (20, 40, 60, 80, and 100 mW/cm²). It was determined that the effect of light created a higher current compared to the dark current, and the reverse bias current increased approximately 80 times depending on the illumination intensity, which confirmed that the produced diode exhibited photoconductive behavior. The ideality factor (barrier height) values obtained as a result of the measurements performed in the dark and 100 mW/cm² light intensity conditions of the produced device were found to be 3.85 (0.68 eV) and 4.54 (0.67 eV), respectively. Transient current measurements also supported this situation and also showed that the device could be enhanced as a photo-capacitor. In addition to these measurements, the effect of frequency and applied voltage on capacitance properties was investigated. The acquired results showed that both conductivity and capacitance were under a strong influence in reverse biasing. Considering all the results together, it has been shown that the used Cu₂MnSnS₄ (CMTS) material and the produced device are a strong candidate to be used in photovoltaic technology.