A Comparative Study of SiO2:TiO2 Composite and SiO2 Film by Sol-Gel Method for Solar Cell Application
Thin films of SiO2 and SiO2–TiO2 composite sol were spin coated on textured monocrystalline silicon wafer and clean glass using Tetraethyl orthosilicate (TEOS) and Titanium tetraisopropoxide (TTIP) as main precursors. For further improvement of the films quality, DMF (dimethylformamide) was added into the solutions to reduce the cracks of the film. The average reflectance of the composite and oxide films was 8.8 and 6.81%, whereas textured monocrystalline silicon (without any coating) wafer having a reflectance of 13.20%. Both the films were annealed at different temperatures ranging from 400 to 900 °C with an interval of 100 °C. After annealing minority carrier lifetime significantly changes from 3.26 to 40.5 µs at 800 °C for oxide film and for composite it was 3.51–45.29 µs at 800 °C. These results show that both the films can be used as an ARC (anti-reflection coating) as well as a passivation layer for solar cell application.
The authors most sincerely acknowledge Ministry of New and Renewable Energy (MNRE), Govt. of India, for financing support for carrying out solar cell related research activity and MSIT, TIG, IIEST for infrastructural support. The authors would also like to thank Mr. Sukhendu Jana and Mr. Sayan Das Assistant professors of MSIT, TIG for their support during characterization of the samples.