CONDUCTIVITY TYPE OF ZNSXSE1-X CRYSTALS AND DEEP TRAPPING CENTERS IN THEM

Statistical analysis of curves of the thermally stimulated luminescenc e, thermally stimulated conductivity, and thermally stimulated emf of ZnSxSe1-x single crystals reveals ten deep carrier-trapping levels, fi ve of the donor type and five of the acceptor type. Although this comp ound has an n-type conductivity, the set of donor and acceptor levels changes as the parameter x varies over the range 0 less-than-or-equal- to x less-than-or-equal-to 0.4, and ultimately a p-type conductivity a rises. This result is confirmed by changes in the signs of the photovo ltage and the Hall voltage. The conductivity type of ZnSe crystals is governed by the deviation from stoichiometry. Annealing the ZnSe sampl es in molten Se at T = 500-900-degrees-C for 5 h stabilizes the p-type conductivity. Annealing in molten Zn under the same conditions gives rise to an n-type conductivity.