RIA: Quantitative Analysis of Polish-Induced Surface Damage in GaAs by X-Ray Diffraction

高度抛光、无损伤的晶圆表面的生产是 通常被认为是制造 半导体器件. 在砷化镓（GaAs）的情况下， 然而，关于微生物学的微观方面知之甚少。 抛光工艺 提出了一项研究计划，将确定 晶片抛光（特别是化学机械抛光）的效果 通常用于GaAs衬底制造中的抛光）上 GaAs中表面和亚表面损伤的水平。 的主要工具， 在这项工作中使用的是X射线衍射， 最大化来自表面的衍射强度的条件， 地下区域。 在一定条件下的衍射等技术 掠入射反射，倾斜布拉格平面衍射，和 三重晶体衍射将用于其灵敏度， 晶片表面和细微的缺陷， 伴随着高质量的化学机械抛光。 的 表面层的晶体结构， 缺陷密度随晶片表面以下深度的变化 将被表征为抛光变量的函数， 晶片旋转速度、样品上的力以及类型和进给速率 化学抛光液的重量。 这项工作将导致一个 定量了解的因素，支配的形成 化学机械抛光过程中的缺陷-器件质量 GaAs衬底

The production of a highly polished, damage-free wafer surface is generally acknowledged as a critical first step in the fabrication of semiconductor devices. In the case of gallium arsenide (GaAs), however, little is known concerning the microscopic aspects of the polishing process. A research program is proposed that will determine the effect of wafer polishing (specifically the chemical-mechanical polishing that is commonly used in GaAs substrate fabrication) on the level of surface and subsurface damage in GaAs. The principal tool to be employed in this work is x-ray diffraction performed under conditions to maximize the diffracted intensity from the surface and subsurface regions. Techniques such as diffraction under conditions of grazing incidence reflection, inclined Bragg plane diffraction, and triple crystal diffraction will be utilized for their sensitivity to both the wafer surface and to the subtle defects that are expected to accompany a high quality chemical-mechanical polish. The crystallographic structure of the surface layer, the strain in the surface, and the density of defects with depth below the wafer surface will be characterized as a function of polishing variables such as wafer rotation speed, force on the sample, and the type and feed rate of the chemical polishing solution. This work will result in a quantitative understanding of the factors that govern the formation of defects during the chemical-mechanical polishing of device-quality GaAs substrates.