High throughput laser isolation of crystalline silicon solar cells

The application of laser technology processing for edge isolation of crystalline-silicon cells is investigated. Two Nd:YAG lasers and a Nd:YVO4 laser operating at 1064 nm or frequency doubled at 532 nm and with different powers are used. The performance of the laser processed solar cells is characterized by measurements of the illuminated IV-curves. Dark IV-curve measurements are accomplished to determine the shunt resistance. It is shown that sufficiently high values of the shunt resistance are achievable. A significant dependency between the fill factor of the cells and the average laser power respectively the point to point overlap, is found. The solar cells used for laser isolation have been processed in an industrial cell fabrication line, and show efficiencies up to 13.2% and fill factors around 77%.