采用单晶位错研究的热弹性模型，计算模拟了垂直布里奇曼法碲锌镉单晶生长过程的应力场，研究了坩埚内壁碳膜的厚度对晶体内热应力的影响．计算结果表明：晶体边缘与坩埚内壁接触位置的热应力远大于晶体中心处的热应力，碳膜厚度的增加，可以显著地减小晶体边缘处的热应力，然而对晶体中心处的热应力影响较小；另外，晶体生长过程中存在两个高应力区，一是固-液界面以下附近的区域，在晶体与坩埚接触的位置出现最大值max1；另一个是晶体底部位置区域，在晶体底部边缘与坩埚接触的位置出现最大值max2，此两处区域的热应力在相转变过程中迅速增加，在随后的晶体冷却过程中热应力持续增大，碳膜厚度的增加可以显著地减小此两个应力区的最大热应力，同时也可以减小max2应力区的面积．
It was simulated that the thermal stress field evolution in the growing crystal during vertical Bridgman CdZnTe crystal growth process with thermal elastic model. The influence of the thickness of the graphite film plating on the inner wall of the quartz crucible on the thermal stress was investigated. The results show that the thermal stress in the edge of the crystal is much larger than the thermal stress in the center of the crystal. With the increase of the graphite film thickness, the thermal stress in the edge of the crystal decreases markedly, while the thermal stress in the centre of the crystal changes little. In addition, there are two maximal von Mises stress regions, one is under the liquid-solid surface, and the maximal stress “max1”is on the peripheral crystal adhered with the inner wall of the crucible, the other is at the bottom of the crystals, the maximal stress “max2” is at the peripheral of the crystal adhered with the inner wall of the crucible. The stresses in both the “max1”and “max2” stress regions increased rapidly during the phase transfer process, and increased continuously during the crystal cooling down process. With the increase of the thickness of the graphite film, both of the “max1” and “max2” stress decreased, and the area of the “max2” stress region (distance from the bottom of the crystal to the minimum stress “min2”) is also decreased.
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| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] |
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