Performance enhancement of thin-film silicon solar cells with nanoporous surface structure and TiO2 passivation layer based on optimal light trapping and surface recombination reducing

Photovoltaic performance of a thin-film silicon solar cell based on light-trapping enhanced and surface-recombination reduced using an optimization of metal-assisted chemical etching (MACE) and TiO₂ passivation was demonstrated. The silver nanoparticles were used as etched mask in MACE process to obtain a nanoporous silicon surface layer. The optical reflectance, dark and photovoltaic current-voltage, external quantum efficiency as a function of the MACE times are measured and compared. Significant improving efficiency of 38% was obtained for the cell with 10-second MACE time and 15-nm-thick TiO₂ passivation.