Direct confirmation of the conduction-band lineup in the CuInSe2-CdS heterojunction solar cell

Abstract
We applied to the CuInSe2‐CdS system the Katnani–Margaritondo rule for estimating heterojunction‐band discontinuities from photoemission measurements. We found that the CuInSe2 conduction‐band edge is 0.2 eV above the CdS conduction‐band edge. This band‐edge lineup explains the efficiency of p‐CuInSe2/n‐CdS solar cells.