Chemical Control of Recombination at Semiconductor Interfaces

这个项目是在分析化学和表面化学的一般领域，在半导体电化学和光化学的子领域。在半导体-电解质界面上的界面电子转移的机制方面将进行实验研究，以测试当前的结行为理论。此外，还将研究电子-空穴复合位点的化学控制。通过研究半导体表面与取代不稳定过渡金属配合物反应的化学性质和由此产生的物理性质，将研究蚀刻硅和砷化镓表面上重要的电表面捕获位点的反应性。将进行半导体复合物相互作用的光谱研究，以阐明修饰表面的金属氧化态、配位壳层和电子性质。将对硅表面的光电钝化进行研究。高注入条件下晶体和非晶硅中的电子传递动力学也将被研究。用精心制备的半导体表面进行实验，以推断大多数载流子的表面浓度与界面电子转移速率之间的关系。将获得关于重要电表面位置的化学信息。这些结果将为理解用于电子器件的半导体加工和太阳能转换提供基础信息。

This project is in the general area of analytical and surface chemistry and in the subfields of semiconductor electro- chemistry and photochemistry. Mechanistic aspects of interfacial electron transfer at the semiconductor-electrolyte interface will be investigated experimentally in order to test current theories of junction behavior. In addition, chemical control of electron-hole recombination sites will be investigated. The reactivity of the electrically important surface trapping sites at etched silicon and gallium arsenide surfaces will be studied by investigating the chemistry and resultant physical properties of semiconductor surfaces in reactions with substitution-labile transition metal complexes. Spectroscopic studies of the semiconductor-complex interaction will be performed to elucidate the metal oxidation state, coordination shell, and electronic properties of the modified surface. Photoelectrochemical passivation of silicon surfaces will be studied. Electron transfer kinetics under high injection conditions in crystalline and amorphous silicon will be also be investigated. Experiments with carefully prepared semiconductor surfaces will be performed in order to deduce relations between the surface concentration of majority carriers and the rate of interfacial electron transfer. Chemical information regarding electrically important surface sites will be obtained. These results will provide information basic to the understanding of the processing of semiconductors for electronic devices and solar energy conversion.