飞行时间二次离子质谱仪二次离子光学系统仿真研究

发布时间：2018-06-17 18:27

本文选题：飞行时间二次离子质谱仪 + 二次离子光学系统　；参考：《吉林大学》2015年硕士论文

【摘要】：作为目前前沿的用于表面成分分析的科学装置之一，飞行时间二次离子质谱仪因具有分辨率高、灵敏度高、分析速度快、测量范围宽、样品消耗少等特点，无论在分析化学、环境科学，还是在生物医学领域，都得到了越来越广泛的应用。飞行时间二次离子质谱仪样品消耗极少这一特点使其更加适用于地质年代学样品的分析。本课题来源于“国家重大科学仪器设备开发专项-同位素地质年代学专用TOF-SIMS科学装置”项目，项目旨在开发应用于地质年代学同位素分析的高精度高分辨率的飞行时间二次离子质谱仪。二次离子光学系统作为飞行时间二次离子质谱仪中的关键部分，主要用于二次离子的提取、调整、聚焦、分离和检测等。二次离子光学系统中的参数变化影响二次离子的运动情况进而影响仪器性能，因而对二次离子光学系统进行仿真研究能够为二次离子光学系统设计和参数选择提供指导和参考。首先，结合飞行时间二次离子质谱仪的原理和结构、二次离子的初始运动情况以及离子光学理论，提出二次离子光学系统的结构和各个组成部分的设计方案，并对各个组成部分的设计方案进行分析。然后，在SIMION软件中建立二次离子光学系统各个组成部分的仿真模型并对仿真条件和操作过程进行阐述，进而对各个部分的参数进行配置，使得能够进行精确的仿真分析。而后，将二次离子光学系统各个组成部分的仿真模型结合，建立二次离子光学系统整体仿真模型，通过仿真研究了二次离子光学系统中透镜电极电压变化对质量分辨率、离子束斑直径变化和传输效率的影响。最后，对仿真结果进行全面而细致的分析，确定了二次离子光学系统中透镜最佳电极电压组合配置。通过仿真模拟和SIMION软件的数据记录功能对数据进行分析和处理，不仅能够观察到二次离子运动轨迹，而且可以得到仿真出的质谱图。以稳定同位素铜离子为研究对象分别进行仿真研究和实验测试，仿真结果与实验结果吻合，证明了二次离子光学系统仿真模型的有效性。
[Abstract]:As one of the most advanced scientific devices for surface component analysis, the time-of-flight secondary ion mass spectrometer has the characteristics of high resolution, high sensitivity, fast analysis speed, wide measurement range and less sample consumption, regardless of whether it is used in analytical chemistry. Environmental science, still in the field of biomedicine, has been more and more widely used. The low consumption of time of flight secondary ion mass spectrometer makes it more suitable for geochronological analysis. This project comes from the project of "National Major Scientific instrument and equipment Development Project-TOF-Sims Scientific device for Isotope Geochronology". The aim of the project is to develop a time of flight secondary ion mass spectrometer with high accuracy and high resolution for geochronological isotope analysis. As a key part of the time-of-flight secondary ion mass spectrometer, the secondary ion optical system is mainly used for the extraction, adjustment, focusing, separation and detection of secondary ions. The change of the parameters in the secondary ion optical system affects the motion of the secondary ion and then affects the performance of the instrument. Therefore, the simulation study of the secondary ion optical system can provide guidance and reference for the design and parameter selection of the secondary ion optics system. First of all, combining with the principle and structure of the time of flight secondary ion mass spectrometer, the initial motion of the secondary ion and the theory of ion optics, the structure of the secondary ion optical system and the design scheme of each component are proposed. And the design of each part of the analysis. Then, the simulation model of each component of secondary ion optics system is established in SIMION software, and the simulation conditions and operation process are described, and then the parameters of each part are configured to make accurate simulation analysis. Then, the simulation model of each component of the secondary ion optics system is combined, and the whole simulation model of the secondary ion optics system is established. The effect of the voltage change of the lens electrode on the mass resolution of the secondary ion optics system is studied by simulation. The effect of ion beam spot diameter change and transmission efficiency. Finally, the simulation results are analyzed comprehensively and meticulously, and the optimal electrode voltage combination configuration of the lens in the secondary ion optical system is determined. Through the simulation and the data recording function of SIMION software, not only the track of secondary ion motion can be observed, but also the mass spectrogram can be obtained. The simulation and experimental tests were carried out with the stable isotopic copper ion as the research object. The simulation results are in good agreement with the experimental results, which proves the validity of the simulation model of the secondary ion optical system.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH843

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