By Viktor Schütz, Scientist, Laser Zentrum Hannover (LZH); Alexander Horn, Head of the Photovoltaics Group, Laser Zentrum Hannover (LZH); Uwe Stute, Manager of the Department Technologies for Nonmetals, Laser Zentrum Hannover (LZH)
In the photovoltaic industry, laser edge isolation (LEI) is a well-established process at the end of the process chain. However, because the cell properties vary from one cell producer to the next, no systematic approach is defined in industry for establishing an efficient isolation groove. Nevertheless, a general approach has to be defined for analyzing the LEI process for silicon solar cells. Besides the material aspects and laser parameters, atmospheric boundary conditions must be considered. This paper presents investigations into the ablation of a specific type of mc-silicon solar cell, and the most suitable laser, as well as the ambient parameters, is determined based on the results of the experiments.