A study of deep centers in Zn1-xMgxSe crystals using deep-level transient spectroscopy

Defects in Zn1-xMgxSe have been studied using deep-level transient spectros copy. The crystalline material with low Mg concentration (x = 0.09, 0.15), obtained by the high-pressure Bridgman method, has a sphalerite structure a nd shows n-type conductivity. A major electron trap was found with a therma l activation energy of 0.37 eV (x = 0.09) and 0.38 eV (x = 0.15), respectiv ely. The trap concentration was 1.5-2.7 X 10(14) cm(-3). From capture measu rements we obtained the electron capture rate c(n) as a function of the tem perature, providing information about the thermal activation energy of the capture process. The capture barrier Delta E-b splits into a high-temperatu re section with E-b = 145 meV and a low-temperature section with a value of 66 meV for E-b. It is assumed that the predominant trap in Zn1-xMgxSe has the same origin as the well-known similar to 0.32 eV trap in ZnSe. (C) 1998 American Institute of Physics. [S0021-8979(98)00121-2].