Emitter Epitaxy for Crystalline Silicon Thin Film Solar Cells with New Contact Methods

Abstract

This paper presents results from the EpiWE with epitaxial emitter combined with new contact techniques based on an approach, where the seed layer is thickened by light induced plating. The high potential of nickel plated and aerosol printed contacts are joined with the advantages of the epitaxial emitter. In spite of some adhesion problems of the grid with nickel plating, high pseudo fill factors and open circuit voltages could be reached. Aerosol printed contacts on epitaxial emitters showed high open circuit voltages up to 622 mV. A good contact formation was possible after a single firing step in contrast to screen-printed solar cells with epitaxial emitters. Best cell results are reached with the highest firing temperature and the lowest chain speed. For the first time, EpiWE solar cells with in-situ emitter and novel industrial relevant contacting techniques are presented.