The Influence of Substrates on the Kinetics of Cadmium Telluride Organmetallic Vapor-Phase Epitaxy

9319186侧面从宏观和微观两个层面研究了同质外延碲化镉的金属有机气相外延动力学。宏观实验探索了衬底取向偏差对OMVPE沉积材料形貌的影响。为了验证台阶是二甲基镉和二异丙基碲反应的关键部位这一假设，建立了台阶生长和丘状生长的速率定律。将开发一种方法来使用速率定律来预测高质量外延薄膜的生长条件。研究了衬底表面微结构对沉积机理中基元反应的影响。采用了扫描隧道显微镜、低能电子衍射和其他表面科学技术。碲化镉薄膜和相关化合物在制造包括光发射器、辐射探测器和光开关的器件方面很有吸引力。目前，它们的制备方法是分子束外延(MBE)，这是一种缓慢、繁琐和昂贵的方法。OMVPE技术的完善应该允许以更大的数量、更低的成本生产这些薄膜，使它们能够被消费者接受。正是为了这个目的，这项努力最终是定向的。***

9319186 Sides This is an investigation of the kinetics of organometallic vapor- phase epitaxy (OMVPE) of homoepitaxial cadmium telluride at both the macroscopic and microscopic levels. Macroscopic experiments explore the effect of misorientation of substrates on the morphology of OMVPE-deposited material. Rate laws for step growth and for hillock growth are developed in order to test the hypothesis that steps are critical sites of reactions of the commonly used sources dimethlycadmium and diisopropyltellurium. A methodology will be developed to use rate laws to predict conditions under which high-quality epitaxial films can be grown. The effect of substrate surface microstructure on the elementary reactions in the deposition mechanism is also investigated. Scanning tunneling microscopy, low-energy electron diffraction, and other surface science techniques are employed. Thin films of cadmium telluride and related compounds are attractive for fabrication of devices involving light emitters, radiation detectors, and optical switching. At present, they are prepared by molecular beam epitaxy (MBE), a method that is slow, cumbersome, and expensive. Perfection of OMVPE techniques should permit higher-volume, lower-cost production of these films, making them acceptable for consumer applications. It is to this end that this effort is ultimately directed. ***