Compound Semiconductor Electrodeposition by Electrochemical Atomic Layer Epitaxy

9400570将开展研究化合物半导体材料薄层电化学原子层外延的Stickney基础研究。在ECALE中，衬底的电化学势被用来控制沉积过程。欠电位沉积现象，即元素的原子层在低于将元素沉积到其自身上所需的电化学电位时形成，被利用并用于逐层原子地沉积化合物半导体材料。每个沉积周期包括溶液引入、电位变化和漂洗的一系列步骤。目前的研究工作包括进行详细的研究，通过研究沉积成分和结构对周期中各个步骤的依赖关系来确定和评估这一过程的机制。精密的表面科学工具被用来跟踪表面覆盖率、成分和化学计量。对电沉积薄膜的晶体结构、取向和质量以及薄膜的发光性能也进行了常规表征。电沉积方法为合成和加工用于太阳能电池、电信和计算机等应用的化合物半导体提供了新的途径，并与现有技术相比提供了几个潜在的优势，如较低的温度沉积和较低的加工成本，因为一旦识别和了解了潜在的基本参数，就可以将电化学过程扩大到大范围。***

9400570 Stickney Fundamental research studies to investigate thin-layer electrochemical atomic layer epitaxy(ECALE) of compound semiconductor materials will be conducted. In ECALE the substrate's electrochemical potential is used to control the deposition process. The phenomenon of underpotential deposition, whereby an atomic layer of an element forms at an electrochemical potential lower than that needed to deposit the element on itself, is exploited and used to deposit compound semiconductor materials atomic layer by layer. Each deposition cycle consists of a sequence involving solution introduction, potential changes, and rinsing. The current research effort involves detailed studies to determine and assess the mechanism of the process through studies of the dependence of deposit composition and structure on the individual steps in the cycle. Sophisticated surface science tools are used to follow surface coverages, composition and stoichiometry. Crystallographic structure, orientation, and quality of electrodeposited films as well as luminescent properties of the films are also routinely characterized. %%% Electrodeposition methodologies offer new pathways to the synthesis and processing of compound semiconductors used in applications such as solar cells, telecommunications, and computing, and provide several potential advantages over existing technologies such as lower temperature deposition, and lower cost processing because of the known capabilities to scale electrochemical processes to large areas once the underlying fundamental parameters have been identified and understood. ***