Rapid optical measurement of surface texturing result of crystalline silicon wafers for high efficiency solar cells application

Surface texturing of crystalline silicon (c-Si wafers) wafers is a frequently used technique in high efficiency solar cells processing to reduce the light reflectance. Measuring the surface texturing result is important in the manufacturing process of high efficiency solar cells because the surface texturing of c-Si wafers is sensitive to the performance of reducing front reflection. Traditional approach for measuring surface roughness of texturing of c-Si wafers is atomic force microscopy. The disadvantage of this approach include long lead-time and slow measurement speed. To solve this problem, an optical inspection system for rapid measuring the surface roughness of texturing of c-Si wafers is proposed in this study. It is found that the incident angle of 60° is a good candidate for measuring surface roughness of texturing of c-Si wafers and y = ?188.62x + 70.987 is a trend equation for predicting the surface roughness of texturing of c-Si wafers. Roughness average (Ra) of texturing of c-Si wafers (y) can be directly determined from the peak power density (x) using the optical inspection system developed. The results were verified by atomic force microscopy. The measurement error of the optical inspection system developed is approximately 0.89%. The saving in inspection time of the surface roughness of texturing of c-Si wafers is up to 87.5%.