Theoretical and experimental analysis on effect of porous silicon surface treatment in multicrystalline silicon solar cells

Graphical abstract: Measured distribution of two-dimensional IQE: (a) before and (b) after PS treatment. - Highlights: • Front surface recombination velocities (S_f) and anti-reflection coating are examined. • Porous silicon on the front solar cell by acid vapors is formed without contact grids destruction. • Conversion efficiency improved by about 5% compared with conventional mc-Si solar cells. - Abstract: As widely known in silicon-based solar cells, the intrinsic parameters are decisive factors for internal quantum efficiency (IQE) and solar cells performances. Particularly, the front surface recombination velocity is one of the most important electrical parameters used to quantify the optoelectronic quality of the solar cells. In this study, the impact of the front surface recombination velocities (S_f) and anti-reflection coating are examined. Theoretical analysis shows that a decrease in S_f enhances the IQE for photons with shorter wavelengths (400–700 nm). Cells with front porous silicon treatment (PS) was made and studied under ambient condition to improve performance of solar cells. In fact, internal quantum efficiency of mc-Si solar cells with PS was enhanced in shorter wavelengths, while the reflectivity was reduced to about 7% after PS treatment and conversion efficiency was improved by about 5% compared with conventional mc-Si solar cells. Furthermore, the laser-beam-induced current (LBIC) mapping shows that the PS treatment improves their quantum response.