DEEP-LEVEL CHARACTERIZATION OF SEEDED PHYSICAL VAPOR TRANSPORT GROWN ZNSE

Deep level characterization of ZnSe grown using the seeded physical va por transport (SPVT) technique is presented for the first time. Deep l evel characterization of ZnSe grown by the high pressure Bridgman tech nique is also presented primarily for the purpose of comparison. Therm ally stimulated current (TSC) measurements reveal several hole trappin g levels in the SPVT samples. TSC from the Bridgman samples, however, reveals a complex structure of overlapping peaks which we were unable to resolve. Thermoluminescence (TL) measurements on Bridgman samples i ndicate that the primary radiative recombination center is the Cu(red) center (E(v) + 0.71 eV). No TL was observed from the SPVT samples des pite the fact that TSC and photoluminescence (PL) reveal the presence of both the Cu(red) and Cu(green) (E(v) + 0.33 eV) centers in both typ es of sample. We present a model which describes the role of these cen ters in both SPVT and Bridgman samples and which explains the lack of TL from the SPVT specimens.