Semi-insulating and n-type substrates quality ZnSe and ZnSe1-xSx (x<0.15) produced by low temperature physical vapour transport

We employed the low temperature physical vapour transport (PVT) method to grow high duality, large (25 mm in diameter) bulk crystals of ZnSe and ZnSe1-xSx(x<0.15). Characterization of the obtained crystals was performed by means of X-ray diffraction. X-ray full with half maximum (FWHM) rocking curves and the energy dispersive X-ray fluorescence (EDXRF) spectrometry. Optical properties were determined from the low temperature near-band-edge photoluminescence and reflection measurements. The photoluminescence was studied also in the conditions of high excitation intensity. A superlinear relation between log(luminescence intensity) and log(excitation intensity) and narrowing of the luminescence line have been observed indicating stimulated emission phenomena. (C) 1997 Elsevier Science S.A.