Surface Defects: Their Role in Atom Transport and Surface Phase Transitions

这项工作旨在表征晶体上的结构缺陷 表面和研究它们在原子输运中的作用 流程. 原子在表面上运动的机制， 产生形态变化和表面相变， 研究了 这项工作的一个主要部分将涉及研究 单晶表面上的原子台阶;它将被关注 在台阶附近有原子结构的，扭结 分布沿着个别步骤，相互作用的对和 步骤组，在质量期间的步骤运动的动力学 输运过程和成核位点的相关性 具有阶跃边缘的相变。 主要实验 结构和动力学研究的方法将是扫描 隧道显微镜，低能电子衍射，和 表面X射线衍射。 实验将在以下两种情况下进行： 半导体和金属单晶。

The work is aimed at characterizing structural defects on crystal surfaces and investigating their role in atom transport processes. The mechanisms by which atoms move on surfaces to produce morphology changes and surface phase transitions will be studied. A major part of the work will involve the study of atomic steps on single crystal surfaces; it will be concerned with atomic structure in the vicinity of steps, kink distributions along individual steps, interactions of pairs and groups of steps, the dynamics of step motion during mass transport processes and the correlation of nucleation sites for phase transitions with step edges. The major experimental methods for the structural and kinetic studies will be scanning tunneling microscopy, low energy electron diffraction, and surface x-ray diffraction. Experiments will be performed both on semiconductors and on metal single crystals.