Surface Crystallography by Low-Energy Ion Scattering

本研究的目的是利用低能离子散射（LEIS）和扫描隧道显微镜（STM）技术确定各种薄膜电子材料的表面结构。 要研究的系统包括：银（001）表面上的铁磁铁和镍的单层薄膜、硅（111）上的铜氯异质外延薄膜、金原子与镓砷（110）的化学相互作用以及金催化的硅表面氧化。 这两种互补的技术将用于构建这些系统及其支撑基底的精确原子分辨率模型。 将开发一种新的数学算法来计算从固体表面散射的低能粒子的角分布。 离子散射装置将被修改以允许散射离子和中性粒子的飞行时间检测。 这将有助于研究离子和表面之间阿秒时间尺度的电荷交换机制。

The objectives of this research are to determine the structures of the surfaces of various thin-film electronic materials using the techniques of low-energy ion scattering (LEIS) and scanning tunneling microscopy (STM). Systems to be studied include: monolayer films of ferromagnetic iron and nickel on silver(001) surfaces, thin heteroepitaxial films of copper-chlorine on silicon(111), the chemical interaction of gold atoms with gallium-arsenic(110), and the gold-catalyzed oxidation of silicon surfaces. The two complementary techniques will be employed to construct accurate atomic resolution models of these systems and the substrates on which they are supported. A new mathematical algorithm will be developed for calculating the angular distributions of low-energy particles scattered from solid surfaces. The ion scattering apparatus will be modified to permit time-of-flight detection of scattered ions and neutrals. This will facilitate study of charge exchange mechanisms on an attosecond time scale between ions and surfaces.