Vertically-movable furnace at short temperature zone and method for growing CdTe crystal by using same

Abstract

The invention provides a vertically-movable furnace at a short temperature zone. The heating furnace only adopts a control system with an iron-chromium-aluminium electric heating wire and a thermoelectric couple, so that a furnace body is simple in structure and low in cost; the vertical height of a heating zone is easy in control, and a heating furnace at the short temperature zone is formed; in addition, since the furnace body is provided with openings at the top part and the bottom part, under the convection action of air, the temperature distribution of the heating zone in the vertical direction takes on a trend of gradual reduction from the middle to the upper side and the lower side so as to be beneficial to reducing the length of a melting zone, improving the zone refining effect of raw materials and reducing the content of impurities in crystals. Furthermore, a silicon carbide material is selected for a support of the heating furnace for supporting a quartz crucible, and the release of latent heat of crystallization on crystal growth interfaces is greatly promoted by utilizing high heat conductivity of silicon carbide, so that a micro-convex solid-liquid interface beneficial to single-crystal growth is obtained. CdTe crystal is grown by utilizing the heating furnace, so that the benefit for eliminating defects of Te precipitation, inclusion and crystal twinning and the like is achieved and the utilization rate of the CdTe single crystal is increased.

Description

technical field [0001] The invention relates to the technical field of heating furnace and crystal growth technology, in particular to a short temperature zone vertical moving furnace and a method for growing CdTe crystal by using the same. Background technique [0002] CdTe crystal is a direct bandgap semiconductor material, which has a higher average atomic coefficient and a larger forbidden band width. The detector made of CdTe crystal has excellent absorption coefficient and count rate, especially it can work at room temperature without any refrigeration, so it has broad application prospects in the field of high-energy detection. [0003] CdTe crystal growth has been developed for many years, and currently there are mainly two preparation processes: Bridgman method and moving heating method. Among them, the Bridgman method grows CdTe crystals faster and can obtain larger-sized crystal materials, but defects such as Te precipitation and inclusions are difficult to overc...

AI Technical Summary

Problems solved by technology

[0004] However, the mobile heating method has disadvantages such as slow crystal growth rate, complicated process and difficult control of interface morphology.

For example, the document "J.Crystal Growth, 2005, vol.284:406-411" reported a method based on the moving heating method to control the growth interface of CdTe crystals by adding a static magnetic field. Although a wavy growth interface was obtained, However, the equipment structure is complex and the growth rate is low, which significantly increases the operating cost

Shanghai University disclosed a device for growing Zn-doped CdTe crystals by moving heating method (patent application number: CN201210349836.3). The furnace body is divided into three temperature zones, which adopt high-frequency electromagnetic induction heating and upper and lower resistance heating respectively. It has certain advantages in crystal purification, but its more temperature control systems make the equipment structure more complex, and it is difficult to guarantee the stability of the temperature field.

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