D. Schmid et al., A COMPREHENSIVE CHARACTERIZATION OF THE INTERFACES IN MO CIS/CDS/ZNO SOLAR-CELL STRUCTURES/, Solar energy materials and solar cells, 41-2, 1996, pp. 281-294
The alignment of energy bands in a Mo/CIS/CdS/ZnO solar cell structure
is presented as derived from individual measurements on the different
interfaces. Special attention is paid to the surface chemistry of the
molybdenum coated substrate. In this study we have performed in situ
analyses on polycrystalline thin films starting with the molybdenum co
ated soda lime glass. The different films have been deposited sequenti
ally under ultra high vacuum conditions and have been analyzed with ph
otoelectron spectroscopy techniques. We have found that the Mo surface
is significantly oxidized. Air annealing at 200 degrees C leads to a
diffusion of sodium through the Mo layer. Mo-O compounds are present a
nd Mo-Se compounds are formed during the evolution of the Mo-CIS inter
face. Band lineups have been determined for the CIS/CdS/ZnO interfaces
of the solar cell structure. We have found no indication for band dis
continuities deteriorating the solar cell device performance.