Performance of CIGS Thin Film Solar Cell with changes in Absorber Layer Thickness and the Back Contact
Adekoya, Abibat Asabi1*, Alabi, Aderemi Babatunde2 and Oni Adewale Adeola3
1&3Department of Physics, Al Hikmah University, Ilorin-Nigeria, PMB 1601, Ilorin
2Department of Physics, University of Ilorin, Ilorin, Nigeria
Email: aadekoya@alhikmah.edu.ng
Corresponding Author: Adekoya, Abibat Asabi
ABSTRACT
The performance of CIGS thin film based solar cell was investigated using a simulation program called Solar Cell Capacitance Simulator (SCAPS 1-D) with variation of thickness of the absorber layer and metal back contacts. The cell structures were based on CIGS semiconductors as the absorber layer, ITO/ZnO as the front contact and CdS as the window layer. The simulation results illustrate that the optimum thickness of the absorber layer with an energy bandgap of 1.1eV should be within 3000nm-3500nm (3-3.5 µm) for a good performance of the solar cell giving efficiency of 16.95% and 17.07% using the common molybdenum back contact. It was also revealed that platinum metal back contacts is preferable due to its non toxic nature when compared with molybdenum and gives a cell with the highest efficiency of 18.44% with just a few thickness of 1000nm compared to palladium and gold metal back contacts with highest efficiency of 11.44% and 14.49% at 2500nm and 3000nm respectively.
Keywords: CdS, CIGS, ITO, Thin film, and ZnO
