Relationship Between Temperature Gradient and Interfacial Shape Stability of CZT Crystal Growth

Abstract

Abstract: CdZnTe crystals are widely used as epitaxial substrates for HgCdTe thin films for infrared detectors and in the fabrication of room temperature nuclear radiation detectors. During crystal growth, the interface shape is closely related to the heat state. Combined with the numerical simulation technique to control the temperature field distribution during CdZnTe crystal growth, the crystal growth procedure of micro-convex solidification interface by vertical Bridgman method and vertical gradient freeze method were designed, and the single crystal rate of CdZnTe crystals was analyzed according to the actual crystal growth experiments. The distribution spectrum of Zn components in the longitudinal section of CdZnTe crystals with equal diameters was obtained by photoluminescence spectroscopy for compositional testing in order to investigate the relationship between the temperature field distribution at the solid-liquid interface and the macroscopic segregation behavior of Zn components. It is found that the temperature gradient distribution on both sides of the solid-liquid interface significantly influences the shape selection and stability of the solidification interface during the crystal growth process, and a larger temperature gradient on the solid-phase side contributes helps to achieve stable crystal growth at the convex interface, thereby increasing the likelihood of growing single crystals.

Key words: CZT crystal, numerical modeling, crystal growth, interface shape, interface stability, macro-segregation

CLC Number:

CAO Cong, LIU Jianggao, FAN Yexia, LI Zhenxing, ZHOU Zhenqi, MA Qisi, NIU Jiajia. Relationship Between Temperature Gradient and Interfacial Shape Stability of CZT Crystal Growth[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(4): 641-648.

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