Role of Plane and Textured TCO Surfaces in Enhancing the Efficiency of Thin Film Amorphous Silicon Solar cell: A Theoretical Approach

In the present work, comparison is made between ITO indium tin oxide) and ZnO (zinc oxide) as TCO layer for the amorphous silicon (a-Si:H) solar cell applications using AFORS-HET simulation software. In order to improve the efficiency of a-Si:H solar cell optimization of band gap of p layer was done along with suggesting the effective light trapping measures which can be adopted in this regard. The optimized value of band gap for p layer 2.1 eV was found for obtaining maximum efficiencies of 14.91 % with ITO and 17.02 % with ZnO as front contact. The further study explored the use of textured TCO surfaces instead of the plane surfaces. The use of textured surfaces of ITO and ZnO enhanced the efficiencies to 15.85 % and 18.10 % respectively at optimized values of the band gap of p, i, and n layers. Hence the overall investigation of a-Si:H solar cells with the idea of maximizing the light trapping using plane as well as textured surfaces of TCO coatings suggests the possibilities for fabrication of efficient a-Si:H solar cells. Our simulation results reveals ZnO as suitable TCO material in order to enhance the efficiencies of solar cell compared to ITO.