Texturing of multicrystalline silicon by laser ablation

Abstract

The application of laser ablation for texturing purposes represents a suitable alternative to common wet chemical texturing schemes. In this paper, a patented texturing scheme, consisting of a laser ablation step followed by plasma-chemical removal of the laser debris has been applied to conventional screen-printed multicrystalline silicon (mc-Si) solar cells. Depending on the laser parameters weighted reflectance values below 20 % are achievable with aspect ratios above 1 (depth to width). The application of the Laser-Plasma texturing scheme to conventional mc-Si solar cells results in an increase of jsc of about 1 mA/cm2 compared to planar etched reference cells indicating the improved optical properties. With a further adaptation of the front side screen-printed metallisation grid, significant improvements of the cell efficiency could be achieved in the future