High throughput processing of CdTe/CdS solar cells

Methods for achieving high throughput and materials yield in processing >13% efficient CdTe thin film solar cells are demonstrated, with emphasis on semiconductor deposition and post-deposition processing. Chemical surface deposition was used to deposit uniform 100 cm² area CdS films 50 nm thick at 0.2 nm/sec, with >80% utilization of solvated Cd species. Vapor transport at 20 Torr was used to deposit dense CdTe films, 1-7 μm thick, onto CdS-coated substrates with >50% utilization in an unbaffled system. Uniform films have been deposited with translation at up to 12 cm/min and static equivalent growth rate >80 pm/min. Vapor CdCl₂ post-deposition treatments yielded solar cells with AM1.5 conversion efficiency >13% for 6 μm thick CdTe and >8% for 1 μm thick CdTe.