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用一种新的气相方法在CdTe衬底上生长了Hg_(1-x)Cd_xTe外延层,该法可得包括整个合金范围(0≤x≤1)的组分。在利用分离元素源的开管系统中已可单独控制决定组分的四个主要参数——衬底温度(400～500℃)、Hg、Cd和Te的分压。借助于一个模型探讨了生长参数的选择,该模型把合金的淀积当作是同时淀积HgTe和CdTe。垂直于外延层表面的方向有一均匀合金组分的初始区,其后为一延伸到衬底的梯度区。吸收边缘测量表明平行于表面的组分十分均匀。所有的层均为n型,其载流子浓度直到几微米的深度时为10~(18)～10~(17)/厘米~3,在它下面一直延伸到衬底里面为浓度大大地减低的区域。
The Hg_ (1-x) Cd_xTe epitaxial layer was grown on a CdTe substrate by a new gas phase method, which included the composition of the entire alloy range (0≤x≤1). The four main parameters that determine the composition - the substrate temperature (400-500 ° C), the partial pressures of Hg, Cd and Te - have been separately controlled in an open tube system utilizing separate element sources. The choice of growth parameters was explored with the aid of a model that treats the deposition of the alloy as simultaneous deposition of HgTe and CdTe. The initial zone of uniform alloy composition is perpendicular to the surface of the epitaxial layer followed by a gradient zone extending to the substrate. Absorbance edge measurements show that the components parallel to the surface are very uniform. All layers are n-type with a carrier concentration of 10-18 (18) / 10-17 / cm3 up to a depth of several microns below which it extends into the substrate to a much lower concentration Area.