大直径HgCdTe 晶体生长研究

大直径(Ф=40mm)HgCdTe晶体生长过程中存在两大难题，一是高汞压引起的生长管爆炸，二是严重的组份分凝引起的组份不均匀。文中对这两大难题进行分析，得到解决这两大难题的方法：一是在生长管外施加一定气压来抵消生长管内的部份汞气压；二是从低熔点的低组分HgCdTe熔体中生长出较高组分的HgCdTe晶体，从而降低生长温度，这样即可降低汞气压，又可减小组分分凝；三是加高组分HgCdTe到低组分HgCdTe熔体中以补充CdTe的消耗，从而生长出纵向组分均匀性好的晶体。

Research for Large-diameter HgCdTe Crystal Growth

Two difficult problems arise in preparation of large-diameter (< = 40mm) HgCdTe crystal ,i. e. high mercury pres-sure leading to explosion of growth ampoule and serious composition segregation leading to compositional unhomogeneity.These problems are analysed in the paper ,and the solutions for these problems are found. The first is to exert suitable pres-sure outside the ampoule to balance the part interior mercury pressure of it. The second is to grow higher composition HgCdTecrystal from HgCdTe melt with lower composition at a lower temperature which can reduce the mercury pressure and decrease the compositional segregation. The final is to add higher composition HgCdTe into lower composition HgCdTe melt to compensate consumed CdTe.