A Laser Welding and Scribing (LWS) Method for a High-Yield Integrated-Type a-Si Solar Cell

Abstract
A new fabrication method for integrated-type amorphous-silicon (a-Si) solar cell submodules, called the laser welding and scribing (LWS) method, was investigated. The conditions for laser scribing and laser welding were calculated from a three-dimensional thermal analysis of a multilayer structure. Calculated results were confirmed by experiment, and the optimum laser power density range for scribing was found to be much wider than that for conventional laser patterning methods. Subsequent connection of adjacent cells in a series by laser welding was also easily performed. This fabrication method has led to a total area conversion efficiency of 10.3% for a 100 cm2 integrated-type a-Si solar cell.