Investigation of the minority carrier lifetime reduction during industrial DC-sputtering of metal seed layers

This works presents the first results of the investigation of the minority carrier lifetime reduction during industrial sputtering of metal seed layers for front side metallization of crystalline silicon solar cells with respect to the cathode performance and the exposure time. Furthermore a method to avoid the reduction of the effective lifetime during sputtering is demonstrated as well as the determination of the ion energy input with the retarding field analysis. All investigations were done by using a new pilot system for inline sputtering. Because of the deposition from below different concepts for substrate holders were used to minimize shadowing effects. Compared to previous investigations a possibility to avoid the lifetime reduction was determined. This underlines the possibility of sputtering for front side metallization.