面向微纳尺度实验力学分析的针尖增强近场拉曼光谱测试系统

Near-field Raman spectroscopy is prospective to be a new and robust method for experimental mechanics in micro-nano scale. However, the currently existing instruments are hardly applicable for mechanical studies, hence there is a need for developing a new near-field Raman equipment, and its accessories as well, specially suitable for micro-nano mechanical measurements and characterizations. This proposal is intend to investigate a set of miniaturized and multi-compatible tip-enhanced near-field Raman spectroscopy system for experimental mechanics in micro-nano scale. Based on the modification of a scan-probe apparatus, the work will build up the backscattering, transmission and lateral scattering Raman conducting components and its associated control systems; design and prosess the micro-loading and clamping devices; and then assemble the overall system, debug all of its functions and complete the calibrations of key parameters. In the research, some pivotal technical problems are going to be solved, such as the multi-control, the stability of the sensitivity, and the optimization of the resolution, the decoupling and recognition of the near field/far-field spectral data, and so on. Based on above, the methodologies for the nanoscale mechanical parameter components analysis, and then the micro-nanoscale collaborative measurement of experimental mechanics, would be presented. Finally, the near-field Raman system will be used in the studies for the multi-scale mechanical properties of some typical micro-nano materials and structures. Through the feedback of the application, the apparatus would be improved.

近场拉曼光谱技术是一种新的具有广泛应用需求的微纳尺度实验力学手段，然而将现有的相关仪器用于力学研究存在较大困难，亟需开发专门适用于微纳尺度力学测量与表征的近场拉曼设备与相关实验装置。本项目面向微纳尺度材料与器件的实验力学分析，拟研发一套小型化、多平台兼容的针尖增强近场拉曼光谱实验测试系统。本研究在改造扫描探针平台基础上，开发、组建包括背反、透射和侧向的拉曼入散射传导组件及其相关控制系统并设计、加工微加载与夹持装置，组装整体系统、调试其各项功能并完成关键技术指标的标定，解决实验系统中包括多重控制、灵敏度稳定与分辨率优化、近/远场光谱力学信息解耦与识别等关键技术问题，在此基础上提出基于所研发仪器系统的纳观尺度力学参量/分量精细分析与微-纳尺度力学参量协同测量实验方法，最后将系统应用于典型微纳米材料与结构多尺度力学性能实验研究，并通过应用实验反馈改进所研发的实验仪器系统。

针尖增强近场拉曼光谱技术是一种具有纳观尺度分辨率的光谱表征方法，但用于力学分析缺少适用的仪器装备和相应的表征方法。本项目科研团队围绕着纳米材料与结构的力学性能高分辨率光谱力学仪器及相关方法开展研究工作，在仪器研发、理论构建和应用研究等方面取得以下研究成果。设计研发了适于力学测量的拉曼外光路系统、扫描探针系统以及专用加载与夹持装置和偏振协同协异控制装置等关键附件，通过系统耦合构建了原位加载与偏振控制下的AFM-Raman系统并初步实现了TERS；提出了基于碳纳米管为传感介质的微区面内应变分量场的精细表征方法与拉曼应变花技术及其标定技术；从晶格动力学出发，构建了面向硅基半导体异质结构任意晶向应力测量的拉曼表征理论并对其进行了实验验证；针对硅锗合金缓冲应变硅纳米多层异质结构，将显微拉曼与针尖增强拉曼相结合，测量了其横截面上界面区域的本证应力延伸度方向的分布规律并给出了其应变梯度；针对单层单晶/多晶石墨烯-PET柔性基底结构，通过测量不同尺寸石墨烯在不同基底载荷情况下的拉曼信息得出其应力分布，表征其界面力学行为，并发现了其界面力学关键参数的尺度效应。本项目完成了计划任务，实现了预期目标。