Optical properties and effects of nitrogen-plasma irradiation of melt grown ZnSe single crystal

N-type zinc selenide (ZnSe) single crystals with a few number of twins and a resistivity less than 1Ωcm have been grown by the vertical gradient freeze method using the pyrolytic boron nitride crucible capsulated in the molybdenum one. Photoluminescence (PL) spectra at 4.2K show an intense free-exciton line, Cu-green and Cu-red or SA emission. The effects of the irradiation of radical species generated from microwave-excited nitrogen plasma have been extensively studied. Capabilities of the nitrogen doping and the effect of ZnSe surface ecthing are discussed for the first time.