Cd doping at the CuInSe_(2)/CdS heterojunction

摘要

The chemical composition of the CuInSe_(2)/CdS heterojunction interface is investigated by angle resolved x-ray photoelectron spectroscopy, Auger electron spectroscopy, and secondary ion mass spectroscopy in combination with selective etching of CdS. We demonstrate that ～0.8 monolayer of Cd is incorporated into the first 1-3 atomic layers of the CuInSe_(2). This is accompanied by significant Cu depletion with respect to In in the same region. The results suggest that Cd_(Cu) defects heavily dope CuInSe_(2) surface n type and cause the observed large band bending on the CuInSe_(2) side of the heterojunction.