Adsorption Sites and Nucleation in Materials Deposition on Silicon and Hydrogen-Terminated Silicon Surfaces

9424296本研究的目标是通过红外振动光谱和扫描隧道显微镜的结合，获得对硅衬底上薄膜成核的原子和分子水平的了解。通过将红外光谱与扫描隧道显微镜相结合，将明确解决硅表面材料沉积和蚀刻方面的一些重要问题--这些问题是理解当前微电子工艺和开发未来技术的基础。首先，重点将放在探索这种方法的局限性上，重点放在砷化镓/硅系统以及硅氧化上。由于这是一个红外强度特别弱的系统，因此该系统将测试实验方法的局限性。硅氧化也将被研究，因为它的技术重要性，而且因为它代表了一种系统，在这种系统中，可以使用CoSi2注入的硅样品在低频下获得高质量和有趣的红外结果。将被研究的系统包括：用水和乙醇氧化Si(100)作为TEOS(乙氧基硅烷)MOCVD过程的模型系统。%这项研究中使用的表征技术提供了表面结合的特定部位的“指纹”，这些技术中的每一种技术的指纹对另一种技术的解释施加了限制，从而比单独使用任何一种技术都可以得出更明确的结论。由于这些材料在电子和光子应用中的重要性，研究基本的化学和物理过程的细节以及了解结构/性质关系的基本特征是很重要的。该项目的一个重要特点是在材料研究的基础和技术领域对学生进行培训。***

9424296 Bent The goal of this research is to obtain an atomic and molecular level understanding of film nucleation on silicon substrates through a combination of infrared(IR) vibrational spectroscopy and scanning tunneling microscopy(STM). By combining IR with STM, a number of important issues in materials deposition and etching on silicon surfaces -- issues which are fundamental to understanding current microelectronics processes and to developing future technologies will be addressed definitively. Initially the focus will be on exploring the limits of the approach with emphasis on the GaAs/Si system as well as emphasis on the oxidation of silicon. The GaAs/Si system will test the limitations of the experimental approach since this is a system where the IR intensities are expected to be particularly weak. Silicon oxidation will also be studied both because of its technological importance and because it represents a system where high quality and interesting IR results at low frequencies using CoSi2-implanted silicon samples can be obtained. The systems that will be investigated include: oxidation of Si(100) by water and by ethanol as a model system for the TEOS (tetraethoxysilane) MOCVD process. %%% The characterization techniques used in this research provide site specific "fingerprints" of bonding at surfaces, and the fingerprint from each of these techniques places constraints on the interpretation of the other which permits more definitive conclusions than would be possible from either of the techniques alone. Because of the significance of these materials for electronic and photonic applications, it is important to study the details of elementary chemical and physical processes, and to understand fundamental features of structure/property relationships. An important feature of the program is the training of students in a fundamentally and technologically significant area of materials research. ***