화학공학소재연구정보센터
Journal of Crystal Growth, Vol.214, 207-211, 2000
Identification of Ag-acceptors in Ag-111/Cd-111 doped ZnTe and CdTe
Nominally undopcd ZnTe and CdTe crystals were implanted with radioactive Ag-111, which decays to Cd-111, and investigated by photoluminescence spectroscopy (PL). In ZnTe, the PL lines caused by an acceptor level at 121 meV are observed: the principal bound exciton (PBE) line, the donor-acceptor pair (DAP) band, and the two-hole transition lines. In CdTe, the PBE line and the DAP band that correspond to an acceptor level at 108 meV appear. Since the intensities of all these PL lines decrease in good agreement with the half-life of Ag-111 of 178.8 h, both acceptor levels are concluded to be associated with defects containing a single Ag atom. Therefore, the earlier assignments to substitutional Ag on Zn- and Cd-lattice sites in the respective II-VI semiconductors are confirmed. The assignments in the literature of the S-1, S-2, and S-3 lines in ZnTe and the X-1(Ag), X-2(Ag)/C-1(Ag), and C-2(Ag) lines in CdTe to Ag-related defect complexes are not confirmed.