Effect of Double Layer (SiO2/TiO2) Anti-reflective Coating on Silicon Solar Cells

Abstract

Silicon based solar cells have been fabricated for single layer SiO2 and double layer SiO2/TiO2 antireflective coatings (ARC) using rf sputtering technique. The results were obtained with nontexturized surface of p-type mono-crystalline silicon (100) substrate and compared with the as-grown Si solar cell. Effect of single layer (SLAR) and double layer (DLAR) AR coatings on the performance of solar cell were characterized through electrical (AM 1.5G, 100 mW/cm2), optical and morphological measurements. The addition of the DLAR initiated 37% improvement in the efficiency of the monocrystalline Si solar cells, compared with 4.5% of the SLAR Si solar cell. Morphological and optical measurements were carried out by atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), Raman spectra and reflectance spectra. A reflection spectrum of DLAR was also measured which shows the minimum reflection of 2.3% at 630 nm with an average reflection of 7% (within the 400-1000 nm range). The results indicated that the DLAR SiO2/TiO2 coatings could be valuable in achieving highly absorbent surfaces in optoelectronic devices as well as in the production of high efficiency low cost silicon solar cells.