Low-cost visible-light photodetector based on Ag/CdSe Schottky diode fabricated using soft chemical solution method

Abstract

The Schottky diode with a configuration of Ag/CdSe/ITO has been fabricated using soft chemical solution method. In this study, uniform nanocrystalline CdSe thin films of about 0.41 μm thickness were grown on ITO coated glass substrate under optimized deposition conditions. XRD and FESEM studies showed that the deposited thin film exhibit nanocrystalline in nature with hexagonal structure and well defined spherical grains with different sizes. The compositional analysis showed that the CdSe film becomes cadmium deficient and selenium richer. Ag/CdSe/Ag ohmic contact and Ag/CdSe/ITO Schottky diode were fabricated for photodetection study. Current-voltage (I-V) measurements of the synthesized Ag/CdSe/Ag ohmic contact showed good photoresponse to visible light indicated that the prepared structure is suitable for photodetector application. The novelty of this work is to use simple and low cost method to fabricate the Schottky diode with a configuration of Ag/CdSe/ITO. The I-V characteristics of Ag/CdSe/ITO Schottky diode were measured under dark and illumination conditions, and it has been observed that the diode exhibits good rectification property. The as-obtained results highlighted that the fabricated Ag/CdSe Schottky diode could be considered as a promising optoelectronic device that can be effectively used in the visible region.