Frequency and voltage dependent electrical and dielectric properties of SiGe thin films for solar cells application deposited on p-type silicon

Abstract

This work presents an experimental study of the electrical and dielectric properties of \( {\text{Si}}_{1 - y} {\text{Ge}}_{y} \) thin films for solar cells application. In order to through light in the electrical conductivity and dielectric properties of the heterojunction, we have carried out the complex impedance spectroscopy technique in the frequency range 10 kHz–1 MHZ at room temperature. The values of the dielectric constant, the real and the imaginary parts of electrical impedance and AC electrical conductivity were found considerably sensitive to frequency. We also studied the photovoltaic parameters of Au/n(SiGe)/p(c-Si) heterojunction solar cell with (y = 0.2). The experimental results show an open-circuit voltage about 0.82 V, a short-circuit current density about 2.1 (mA/cm2) and an efficiency of the cell about 1.3%. The results indicate that the Au/n(SiGe)/p(c-Si) heterojunction structure might be promising for the solar cell applications.