The Molecular Kinetics of the Organometallic Vapor-Phase Epitaxy of II-VI Materials

研究了二甲基镉和二乙基碲分解沉积碲化镉的机理和动力学。初步结果表明，沉积是由有机金属分子吸附在烷基上的催化反应发生的。在超高真空条件下，测定了二甲基镉和二乙基碲在（2x8）砷化镓（100）上吸附和分解的基本动力学。内反射红外光谱和x射线光电子能谱鉴定了吸附物质并测量了它们的表面覆盖率。程序升温解吸用于表征分解动力学。动力学参数成为可能，他们被纳入数学模型适合设计，优化，和控制有机金属气相外延（OMVPE）反应器。本项目提供了OMVPE工艺和反应器模型所需的基础数据，并开始了这些模型的开发。OMPVE是一种非常有前途的技术，用于生产化合物半导体的层状结构，形成高速场效应晶体管、发光二极管、固态激光器、红外探测器和太阳能电池等电子和光子器件的有源区域。

The mechanism and kinetics of the deposition of cadmium telluride from the decomposition of dimethylcadmium and diethyltellurium are determined. Preliminary results indicate that deposition occurs by a catalytic reaction consisting of the adsorption of the organometallic molecules on the alkyl groups. In this study, the elementary kinetics of adsorption and decomposition of dimethylcadmium and diethyl tellurium on (2x8) gallium arsenide (100) are determined in ultrahigh vacuum. Internal-reflection infrared spectroscopy and X-ray photoelectron spectroscopy identify the adsorbed species and measure their surface coverages. Temperature-programmed desorption is used to characterize the decomposition kinetics. A kinetic parameters become available, they are incorporated into mathematical models suitable for the design, optimization, and control of organometallic vapor-phase epitaxy (OMVPE) reactors. This project provides the fundamental data needed for process and reactor models of OMVPE, and makes a start on developing these models. OMPVE is a very promising technology for producing layered structures of compound semiconductors, which form the active region of such electronic and photonic devices as high-speed field-effect transistors, light-emitting diodes, solid-state lasers, infrared detectors, and solar cells.