SEMIINSULATING AND N-TYPE SUBSTRATES QUALITY ZNSE AND ZNSE1-XSX (X-LESS-THAN-0.15) PRODUCED BY LOW-TEMPERATURE PHYSICAL VAPOR 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 (ED XRF) spectrometry. Optical properties were determined from the low tem perature near-band-edge photoluminescence and reflection measurements. The photoluminescence was studied also in the conditions of high exci tation intensity. A superlinear relation between log(luminescence inte nsity) and log(excitation intensity) and narrowing of the luminescence line have been observed indicating stimulated emission phenomena. (C) 1997 Elsevier Science S.A.