Surface photovoltage analyses of Cu(In,Ga)S2/CdS and Cu(In,Ga)S2/In2S3 photovoltaic junctions

Abstract

Spectrally dependent surface photovoltage measurements were performed with repetitive regime on Cu(In,Ga)S2 absorbers and on Cu(In,Ga)S2/CdS and Cu(In,Ga)S2/In2S3 junctions. The results are correlated to current-voltage investigations of the respective completed solar cells. The measurements show the presence of a space charge region in the bare Cu(In,Ga)S2 absorbers due to a high density of surface states. It is found that deposition of CdS increases the band bending whereas deposition of In2S3 does not change it.