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Bridgman-grown, nominally undoped CdTe crystals were doped with Ag by implanting radioactive 111Ag. Photoluminescence spectra of the crystals show a donor-acceptor pair (DAP) line at 1.491 eV. The decrease of the intensity of this line with a half life of T1/2=(7.2±0.4) d is in good agreement with the half life of the β− decay of 111Ag to 111Cd of 7.45 d. This decrease is not caused by the aging behavior of Ag which was reported in the literature. The data show that the involved acceptor defect contains exactly one Ag atom and confirm the earlier assignment of the acceptor to the AgCd defect. Based on the DAP line at 1.491 eV, the spectra did not reveal a contamination of the CdTe crystals by stable Ag.

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 μm during diffusion anneal at about 550 K. Radio-tracer experiments using 111Ag 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.

Acceptor‐defect and acceptor‐impurity complexes in GaAs have been studied by perturbed angular correlation spectroscopy. In n‐type GaAs close Cd‐S pairs were formed; the temperature dependence of the related electric field gradient indicates an electrically inactive Cd‐S complex. After a hydrogen plasma exposure of GaAs a distinct Cd‐defect complex has been observed. Similarly, plasma‐induced configurations were also formed in InP and GaP.