Development of a High Resolution X-Ray Analysis Facility forAdvanced Materials

X射线测量为许多材料系统提供了非破坏性的结构信息。高分辨率的衍射测量决定了样品的完好性、成分和应变调制以及几个原子平面上的界面突变性。X射线反射率测量解决了薄膜系统中的电子密度调制和界面粗糙度问题。这些问题与半导体外延异质结构、器件结构和块体材料的生长和加工高度相关。物理信息，包括应变和材料完好性对光学和电子性能的影响，也是定量确定的。在其他领域，这些技术加强了对高温合金和用溶胶凝胶法沉积的陶瓷薄膜的共格应变的研究。在这个项目中，我们将开发一台具有高、低温两个阶段的高分辨率X射线衍射/散射表征设备。该设施应包括晶片测绘能力和模拟软件。主要研究内容包括：硅-锗多层膜和器件结构，碲镉汞的生长动力学和结构性质，应变与III-V多层膜的光学和输运性质的关系，以及沉淀硬化高温合金中的失配应变。

X-ray measurements provide non-destructive structural information for many materials systems. High resolution diffraction measurements determine sample perfection, compositional and strain modulation, and interface abruptness over a few atomic planes. X- ray reflectivity measurements address electron density modulations and interface roughness in thin film systems. Such issues are highly relevant to the growth and processing of semiconductor epitaxial heterostructures, device structures, and bulk materials. Physical information, including the effect of strain and materials perfection on optical and electronic properties, are also quantitatively determined. In other fields, these techniques enhance the study of coherency strains in superalloys and of ceramic thin films deposited by sol-gel methods. In this project, we will develop a high resolution x-ray diffraction/scattering characterization facility with both high and low temperature stages. The facility shall include wafer mapping capabilities and simulation software. Major research proposals involving Si1icon- germanium multi-layers and device structures, the growth kinetics and structural properties of HgCdTe, the relationship between strain and optical and transport properties in III-V multi-layers, and misfit strain in precipitation hardened superalloys are presented.