And semiconductor alloys as competent materials for opto-electronic and solar cell applications: a comparative analysis

Abstract

ZnO1−xTex ternary alloys have great potential to work as a photovoltaic (PV) absorber in solar cells. ZnO1−xSx is also a ZnO based alloy that have uses in solar cells. In this paper we report the comparative study of various parameters of ZnO1−xTex and ZnO1−xSx for selecting it to be a competent material for solar cell applications. The parameters are mainly being calculated using the well-known VCA (virtual crystal approximation) and VBAC (Valence Band Anti-Crossing) model. It was certainly being analysed that the incorporation of Te atoms produces a high band gap lower than S atoms in the host ZnO material. The spin-orbit splitting energy value of ZnO1−xTex was found to be higher than that of ZnO1−xSx. Beside this, the strain effects are also higher in ZnO1−xTex than ZnO1−xSx. The remarkable notifying result which the paper is reporting is that at a higher percentage of Te atoms in ZnO1−xTex, the spin-orbit splitting energy value rises above the band gap value, which signifies a very less internal carrier recombination that decreases the leakage current and increases the efficiency of the solar cell. Moreover, it also covers a wide wavelength range compared to ZnO1−xSx.