Wide-Gap Cu(In,Ga)Se2 Solar Cells with Zn(O,S) Buffer Layers Prepared by Atomic Layer Deposition

• DOI: 10.1143/jjap.51.10nc15
• Publication Date: 2012-10-23T02:29:36Z
• Authors: Kazuya Nakashima; Toyokazu Kumazawa; Taizo Kobayashi; Takahiro Mise; Tokio Nakada
• Keywords: Buffer (optical fiber); Open-circuit voltage; Band offset; Deposition

Wide-gap Cu(In 0.4 ,Ga 0.6 )Se 2 solar cells with Zn(O,S) buffer layers deposited by atomic layer deposition (ALD) technique have been investigated. The band-gap energy ( E g ) of the estimated optical transmission and reflection measurements was varied from 3.2 to 3.6 eV. sulfur (S)-poor showed a low open-circuit voltage V OC owing cliff nature conduction band offset (CBO). In contrast, S-rich short-circuit current density J SC spike CBO. Even if CBO values were adequate, best cell efficiencies considerably low. These results suggest that main cause for is not interface recombination at Zn(O,S)/Cu(In,Ga)Se interface, but mainly bulk in Cu(In,Ga)Se (CIGS) absorber layer.