CAJ | 학술논문

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.
랍만광보분변솔시관계도종광보중제취출양품결구신식적관건삼수,고분변랍만광보능구제공경다、경정세적양품유관신식.재차전면분석료현대고분변랍만광보의중결정광보분변솔적각삼수,변석료역우혼효적분변솔화색산도개념.용이론분석화실험결과설명광책밀도여광보분변솔적관계이급채용고밀도광책증진광보분변솔소수도적한제、여하이용장초장광책증진광보분변솔이불손해의기통광효솔、입사협봉관도대광보분변솔급령민도적영향,재차기출상여하구득일개합리적평형선택;병차용불동배치적현대신형랍만광보의실험연구료다층규결구중적응력분포화단벽탄납미관관경분포,실험결과청석지좌증료이상분석,병충분설명료랍만광보측량중선택분변솔적중요성.
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 crystalline layer of Si on an Si_xGe_(1-x) substrate.It is possible to use Raman spectroscopy to probe the stress in the Si_xGe_(1-x) and Si layers at the same time.The parameter to monitor the stress is the position of the Si-Si vibrational mode in Si_xGe_(1-x) and Si.Such a measurement requires high spectral resolution because the peaks exhibit very subtle shifts.The authors' results clearly demonstrate 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 diameters 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 hands,which leads to a correct analysis of the diameter distribution.