Highly efficient large area thin film CdS/CdTe sub-module [solar cells]

From 1995, Matsushita Battery Co., Ltd has been developing a low cost and efficient technologies to fabricate a thin-film CdS/CdTe solar cell. Earlier, the authors reported a conversion efficiency of 10.5% for a middle size sub-module (1376 cm/sup 2/) [1] and 16.0%, efficiency for 1 cm/sup 2/ cells. They report here a highly efficient large area CdS/CdTe solar cell (11.0%, 5413 cm/sup 2/) sub-module. The key technologies to fabricate the high efficiency modules are the suppression of the diffusion of F ion into CdS layer, CdTe stoichiometry, the film thickness and uniformity of all the constituent layers such as SnO/sub 2/:F, CdS and CdTe prepared under atmospheric pressure conditions.