分布式碲锌镉晶体制备材料区熔提纯炉研究

Research on Distributed Zone Melting Purification Furnace for Material Preparation of CdZnTe Crystal

针对远红外探测器衬底制造对高品质碲锌镉单晶材料的需求,为了满足高品质碲锌镉单晶生长对高纯度原材料的需要,基于区熔提纯原理与工艺实现方法设计出一种由区熔炉炉体、移动加热装置、气路系统和电气控制系统等组成的分布式碲锌镉晶体制备材料区熔提纯炉。采用氢气除杂、氮气保护和伺服机构控制加热温度场移动的方法来实现区熔提纯。在区熔窄区宽度为15 mm和倾斜角度为7°的条件下,开展了碲、锌和镉等原材料的区熔提纯实验。结果表明,当加热温度高于材料熔点50 K且移动速度为0.006 mm·s^(-1)时,区熔加热装置往复移动10次以上,可将碲锌镉晶体制备所需的原材料纯度由6N(99.9999%)提高到7N(99.99999%);分布式碲锌镉晶体制备材料区熔提纯炉的加热温度、加热装置移动速度和移动稳定性较好。

In response to the demand for high-quality CdZnTe single crystal materials in the preparation of far-infrared detector substrates,a distributed zone melting and purifying furnace composed of zone melting furnace body,moving heating device,gas circuit system and electrical control system for preparing material of CdZnTe crystals is designed based on the principle and process realization method of zone melting purification in order to meet the need of high-purity raw materials for the growth of high-quality CdZnTe single crystals.The zone melting purification furnace is realized by the method of hydrogen impurity removal,nitrogen protection and servo mechanism to control the movement of the heating temperature field.The zonal purification experiments of tellurium,zinc and cadmium are carried out under the condition that the zonal narrow zone width is 15 mm and the incline angle is 7°.The results show that when the heating temperature is 50 K higher than the melting point and the moving speed is 0.006 mm·s^(-1),the purity of the raw material for CdZnTe crystal preparation can be increased from 6N(99.9999%)to 7N(99.99999%)if the zone-melting heating device moves more than 10 times.The heating temperature,the moving speed of the heating device and the moving stability of this furnace are better.