原子薄膜厚度的微变布儒斯特角偏光测量方法研究

原子或近原子尺度制造是现代制造发展的未来方向，其核心技术之一是材料厚度的原子量级可控增减或转移。然而，原子量级薄膜受尺寸效应和界面效应的影响显著，信号微弱，性质多变，测量难度大。现有的光学、扫描电镜、原子力显微镜等技术在测量性能、效率、使用环境等方面存在局限性，无法满足精准高效的测量要求，新型制造工艺亟需发展超精密厚度测量技术。本项目聚焦原子薄膜厚度精准测量问题，提出运用超薄膜复合结构在等效布儒斯特角附近的光学响应与薄膜厚度的超灵敏强关联性，发展微变布儒斯特角偏光特性测量方法，并从原子薄膜复合结构的数学建模、原子量级厚度变化对材料偏光特性的作用机理与规律、亚毫弧度角度分辨的偏光特性精密测量技术研发，和面向典型超精密加工工艺的实验研究等方面展开工作。项目将为原子尺度制造提供一种精密、高效、适用性好的厚度测量方案，并推动该尺度下光学测量方法的基础研究。

Atomic or close-to-atomic scale manufacturing is the future of manufacture. Atomic-thickness film (Å-film) is a key and general part for atomic scale manufacturing as it has both microscopic thickness and macroscopic area. To realize thickness controllable fabrication of the Å-film, thickness measurement method with subatomic precision is necessary. But signals induced by the addition or subtraction of monolayer are very small and easily various to working conditions. The signals are normally buried in those noises from large volume substrate and effects of interfaces. Although several techniques, like optical methods, scanning electronic microscopy, and atomic force microscopy, have been successfully applied to measure the thickness of ultrathin films, they still have many limits in testing performance, operation requirement, and working efficiency. There is no atomic precision thickness measurement solution available for mass production in the near future. Focused on the scientific problem mentioned above, this proposal aims to develop a new high thickness sensitivity method based on a strongly mutual interaction between the structure and the optical properties of thin films at near Brewster angle. The research mainly includes four parts: optical model and its optical properties of Å-film, influence and mechanism of the thickness change in an atomic level on the film’s optical properties, development on new film thickness measurement method based on an optical polarization theory at near Brewster angle, building up a prototype of the new instrument, and an experimental research to test the prototype in different manufacturing processes. The success of this proposal will lead to a step forward for the development of optical measurement technique and, for sure, provide a precise, efficient, robust, and valuable solution to atomic scale manufacturing.