Development of a rapid thermal annealing process for polycrystalline silicon thin film solar cells on glass

In this report, we discuss the influence of rapid thermal annealing RTA on the performance of polycrystalline Si poly Si thin film solar cells on glass where the poly Si layers are differently prepared. The first part presents a comprehensive study of RTA treatments on poly Si thin films made by solid phase crystallization SPC standard material of CSG Solar AG, Thalheim . By varying both plateau temperature up to 1050 C and duration up to 1000 s of the annealing profile, we determined the parameters for a maximum open circuit voltage VOC . In addition, we applied our standard plasma hydrogenation treatment in order to passivate the remaining intra grain defects and grain boundaries by atomic hydrogen resulting in a further increase of VOC. We found, that the preceding RTA treatment increases the effect of hydrogenation already at comparable low RTA temperatures. The effect on hydrogenation increases significantly with RTA temperature. In a second step we investigated the effect of the RTA and hydrogenation on large grained poly Si films based on the epitaxial thickening of poly Si seed layer