Shift of Ag diffusion profiles in CdTe by metal/semiconductor interfaces

Metal layers deposited on the surface of the semiconductor CdTe effect a shift of the concentration profile of Ag dopants in CdTe by several 100 mu m during diffusion anneal at about 550 K. Radio-tracer experiments using Ag-111 show that this effect occurs in the case of Al, Ni, Cu, and Au layers. A preliminary explanation relates the effect to an enhancement of the diffusion of Ag atoms in CdTe caused by Cd self-interstitials that are generated at the metal/semiconductor interface. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4709393]