R. Pandey, R. Chaujar
Delhi Technological University, India
pp. 199 - 202
Keywords: back-contact back-junction (BC-BJ), band gap, recombination, silicon-germanium (SiGe), solar cell
In this work, an ultra-thin, Back-Contact Back-Junction (BC-BJ) Crystalline Silicon-Germanium (SiGe) solar cell device structure called BC-BJ c-SiGe solar cell has been proposed. The results, are compared with conventional BC-BJ silicon cell. SiGe is used as an alternative of silicon, its processing is simple because the physical and electrical properties of silicon and germanium are similar. Also SiGe possesses higher mechanical strength, and suppresses the high intensity degradation of solar cell under illumination .Proposed device shows, enhanced photovoltaic properties. The external Quantum Efficiency (EQE) > 80% in the spectrum range of 430-670 nm wavelength have been achieved. Results reveal, proposed device is less affected by carrier recombination, resulting in 13.5 % power conversion efficiency (PCE).The lower recombination is observed in novel device. The proposed device shows 26% higher EQE compared to silicon cell. Also, the maximum output power density (Pm) of 10µm thick silicon cell and 5µm thick SiGe cell was approximately same, 11.7mW/cm2 in 10µm thick silicon cell and 11.3mW/cm2 in 5µm thick SiGe cell, respectively .Result shows, novel BC-BJ crystalline SiGe Solar cell will be a good candidate for cost-effective solution for energy efficient applications.