Structural Properties of Cd_1-xMg_xTe and Cd_1-x-yMg_xMn_yTe Crystals

Abstract

Electron probe microanalysis and X-ray diffraction studies have been performed on samples of ternary Cd1-x ΜgxΤe (0.05 < x < 0.09) and quaternary Cd1-x -y Mgx Mny Τe (0.025 < x < 0.4; 0.025 < y < 0.7) alloys. The investigated samples were cut from 24 different ingots grown by Bridgman method. Microprobe examinations Iave revealed significant differences between actual and nominal content of Mg along the longitudinal direction for both ternary and quaternary ingots. In contrast to Mg, for most Cd1-x -y Μgx Μny Τe samples the actual Mn content was within ±5% of nominal content. The lattice constants have been determined by X-ray powder diffraction method. Whereas Cd1-x-yMgxΜnyTe samples exhibit only zinc blende crystal structure for the entire region of x and y investigated, the Cd1-x Mgx Τe alloy has two different structures depending on Mg content; a zinc blende structure below x = 0.5 and a wurtzite structure above it. In both alloys the lattice constant decreases with increasing Mg content.

Ellipsometric studies of Cd1−xMgxTe (0⩽x⩽0.5) alloys

“…Details of sample growth and characterizations are described in Ref. 5. Pseudodielectric function spectra ͗()͘ϭ͗ 1 ()͘ ϩi͗ 2 ()͘ were measured at room temperature from 1.5 to 6.0 eV using an automatic spectroscopic rotating-analyzer ellipsometer ͑RAE͒.…”