Anti-Reflection Coating Based on Mullite for Silicon Solar Cells

Antireflection coatings (ARCs) increase the absorption of light and, therefore, the conversion efficiency of solar cells. Mullite was chosen as the ARC material for a silicon (Si) solar cell and was synthesized by melting a charge consisting of a mixture of Al₂O₃ and SiO₂ at a component concentration of 75 and 25 wt.%, respectively. It has been established that the integral reflection (R_S) of ARCs based on mullite is about 6.0 times less than for silicon and about 2.5 times less than the R_S of a coating based on silicon nitride. The electric characteristics measured by a solar simulator before and after vacuum deposition of a mullite film with a thickness of 80–85 nm on solar-cell samples showed an increase of short-circuit current up to 49.5% and a rise in efficiency up to 6.8%.