Effective Passivation of Large Area Black Silicon Solar Cells by SiO2/SiNx:H Stacks

The performance of black silicon solar cells with various passivation films was characterized. Large area (156 x 156 mm(2)) black silicon was prepared by silver-nanoparticle-assisted etching on pyramidal silicon wafer. The conversion efficiency of black silicon solar cell without passivation is 13.8%. For the SiO2 and SiNx:H passivation, the conversion efficiency of black silicon solar cells increases to 16.1% and 16.5%, respectively. Compared to the single film of surface passivation of black silicon solar cells, the SiO2/SiNx:H stacks exhibit the highest efficiency of 17.1%. The investigation of internal quantum efficiency (IQE) suggests that the SiO2/SiNx:H stacks films decrease the Auger recombination through reducing the surface doping concentration and surface state density of the Si/SiO2 interface, and SiNx:H layer suppresses the Shockley-Read-Hall (SRH) recombination in the black silicon solar cell, which yields the best electrical performance of b-Si solar cells.