JSC “Giredmet”, Moscow, Russia:

M. B. Grishechkin, Researcher
I. A. Denisov, Head of Laboratory, e-mail: IADenisov@rosatom.ru
A. A. Silina, Researcher
N. I. Shmatov, Leading Researcher

This paper investigates the seeding peculiarities during the crystals Cd_1–xZn_xTe (х ~ 0.04) growing by vertical oriented Bridgman crystallization in glasscarbonic crucibles with various shapes and sizes. There was carried out the numerical modelling of the conditions of heat- and mass-transfer on all stages of the growing process. On the seeding stage, the isotherm, matching with the solidus temperature х ~ 0.04 (1098 ^оС), is convex-concave in all cases. Increasing the part of crystallized phase changes the isotherm shape through the convex in melt to the concave in crystal for crucibles with diameters 50–51 mm and 50–68 mm. Considering the crucible with diameter 65–85 mm, the isotherm becomes the convex in melt with the temperature of 1098 ^оС and has this shape during the whole growing process. The numerical modelling data optimized the seeding conditions during the crystal Cd_1–xZn_xTe growing. Analysis of ZnTe distribution in grown crystals showed the correlation of the crystallization edge shape with the shape of isotherm of crystal solidus х ~ 0.04, obtained by the calculation conditions. Introduction of the additional stage of grinding of synthesized polycrystals and reloading in raster container does not lead to the decreasing of grown ingot purification. Structural, electrophysical and optical characteristics of obtained material meet the requirements to the material for the manufacturing of bottom layer for liquid phase epitaxy of photo-sensible layers Hg_1–yCd_yTe.
This work was carried out with the financial support of the Ministry of Education and Science within the Agreement about the subsidiary on 21 October 2014 No. 14.576.21.0055 (unique identifier RFMEFI57614X0055).

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