Assessment of crystal quality, homogeneity in composition, Tellurium precipitates/inclusions concentration and optical transmission of Cd(1-x)Zn(x)Te (0 ≤ x ≤ 0.1)

A.M. MARTINEZ; A.B. TRIGUBÓ ; R. D´ELÍA ; E. HEREDIA; R. RAMELLI; R. GONZÁLEZ ; F. AZA; U. GILABERT

JOURNAL OF CRYSTAL GROWTH

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2012

0022-0248

Ingots of Cd1-xZnxTe (0 ≤ x ≤ 0.1) were grown by the Bridgman method using different rates in order to find optimum conditions for single crystal growth. The crystal quality was studied by chemical etching; the chemical composition using a wavelength dispersive electron microprobe; the concentration of Te precipitates by differential scanning calorimetry and optical transmission with Fourier transform of infrared spectroscopy. It was observed that the slower grown ingots have at most three grains of different crystallographic orientation, with the best quality crystals, although the average dislocation density is similar in all cases and corresponds to good quality materials. The electron microprobe results indicate that the composition has excellent homogeneity in the ingot central part. The concentration of tellurium precipitates/inclusions in all ingots is less than the minimum value of the measurements (0.25% m/m) enabled by the used DSC equipment. Infrared transmittance is excellent in CdTe alloyed with 2 or 5 At% Zn with the optical transmission in the range between 60 and 70%, meanwhile for CdTe the range is between 50 and 55%, resulting in this case affected by the presence of precipitates / inclusions of tellurium.