现代高分辨拉曼光谱仪的配置及应用研究  

Study on the Configuration and Applications of High Spectral Resolution Raman Spectrometer

作　　者：刘照军[1] 赵存华[1] 韩礼刚[1] 莫育俊[2] 

机构地区：[1]洛阳师范学院物理与电子信息学院,河南洛阳471022 [2]河南大学物理与电子学院,河南开封475004

出　　处：《光谱学与光谱分析》2010年第2期567-570,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(10674041);2007河南省科技计划项目(072300410330)资助

摘　　要：拉曼光谱分辨率是关系到从光谱中提取出样品结构信息的关键参数,高分辨拉曼光谱能够提供更多、更精细的样品有关信息。在此全面分析了现代高分辨拉曼光谱仪中决定光谱分辨率的各参数,辨析了易于混淆的分辨率和色散度概念。用理论分析和实验结果说明光栅密度与光谱分辨率的关系以及采用高密度光栅增进光谱分辨率所受到的限制、如何利用长焦长光栅增进光谱分辨率而不损害仪器通光效率、入射狭缝宽度对光谱分辨率及灵敏度的影响,在此基础上如何求得一个合理的平衡选择;并且用不同配置的现代新型拉曼光谱仪实验研究了多层硅结构中的应力分布和单壁碳纳米管管径分布,实验结果清晰地佐证了以上分析,并充分说明了拉曼光谱测量中选择分辨率的重要性。In the present paper the authors studied theoretically and experimentally the relationship between spectral resolution and grating density, the limitations to improve the spectral resolution by using high density grating, the use of longer focal length grating to increase spectral resolution without compromising instrument throughput and the effect of slit width on spectral resolution and sensitivity. Finally, two experiment results were provided to show why higher spectral resolution is important to ensure that critical information is not lost during a Raman measurement. Stressed silicon was produced by growing a thin crystal- line layer of Si on an SixGel , substrate. It is possible to use Raman spectroscopy to probe the stress in the Si^Gel-x and Si lay- ers at the same time. The parameter to monitor the stress is the position of the Si-Si vibrational mode in Si.Gel , and Si. Such a measurement requires high spectral resolution because the peaks exhibit very subtle shifts. The authors＇ results clearly demon- strate that the resolution offered by a high density grating is necessary to properly monitor the very small frequency shift of this cap-layer Si-Si mode in order to properly characterize the strain structure. The Raman band around 180 cm 1 is assigned to the radial breath mode of single wall carbon nanotube （SWCN）. By measuring the frequencies excited with different laser, the diam- eters of the sample can be obtained. Practically, sample is always composed of SWCN with different but very close diameters and their Raman bands might overlap together and are difficult to determine the frequencies. The authors＇ results showed that only higher resolution with the long focal length spectrometer can give accurate number and frequencies of Raman bands, which leads to a correct analysis of the diameter distribution.

关 键 词：光谱分辨率 单色仪密度 光栅焦长 狭缝宽度 高分辨拉曼光谱 

分 类 号：TH744.1[机械工程—光学工程]