Development of STM-TOF mass analyzer and its application for material analysis

STM-TOF质量分析仪的研制及其在材料分析中的应用

• 批准号: 09555263
• 负责人: OKAZAKI Satoshi
• 金额: $ 8.26万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555263/
• 关键词: TOF mass analyzer; TOF surface analysis; Laser excitation; Ion beam excitation; STM-TOF; Ion dissociation; 走査トンネル顕微鏡; 飛行時間型質量分析計; 表面局所質量分析; 材料機能評価; ナノキャラクタリゼーション

In this project, we developed high sensitive and high resolute TOF-MS for nano-surface analysis. The aim of our study is to develop the new TOF analyzer system that can analyze chemical composition, chemical structure and chemical state of nano-order sample's surface in atomic or molecule size level, by combining TOF-MS with UHV-STS/STM.First, we developd the TOF-MS combined UHV-STS/STM after many revisions and trials, Next, by introducing small size pulse ion source to the TOF, we studied TOF-MS based on ion-beam excited dissociation. In addition, we studied and built up the measurement system that can be used laser assist ionization method in which surface of sample was irradiated with laser pulse. Especially, in these cases, about STM measurement, we got basis date about the relation between the current and the distance between tip and sample, by varying bias voltage in wide range. In the laser assist ionization method, we focused the excitation beam of YAG laser at 355 nm onto the top of tip in the STM measurement system. With this treatment, we could find the correlation between the intensity of dissociated ion from the surface of sample and intensity of laser pulse. More over, based on these results, using bias voltage and current of tip as the parameters, we found the relation between parameters and intensity of dissociated ion originated from laser pulse, and got useful knowledge about effective ionization suitable for variable materials.At present, we are improving the focal electric field and found the optimal condition to develop the efficiency TOF detector, and studying to translate the distribution of desorbed ion into two dimensional picture by tip scanning measurement.

本项目研制了高灵敏度、高分辨的飞行时间质谱仪，用于纳米表面分析。本课题的研究目的是将飞行时间质谱（TOF-MS）与超高真空STS/STM技术相结合，研制出一种能在原子或分子尺度水平上分析纳米级样品表面化学成分、化学结构和化学状态的飞行时间质谱分析系统。首先，我们经过多次修改和试验，研制出飞行时间质谱与超高真空STS/STM技术相结合的飞行时间质谱分析系统。研究了基于离子束激发解离的飞行时间质谱。另外，我们还研究并建立了一套激光辅助电离法的测量系统，该系统是用激光脉冲辐照样品表面。特别是在STM测量中，通过在很大范围内改变偏置电压，得到了电流与针尖到样品距离关系的基本数据。在激光辅助电离方法中，我们将YAG激光的激发光聚焦到STM测量系统的针尖顶部。通过这种处理，我们可以发现样品表面解离离子的强度与激光脉冲强度之间的相关性。在此基础上，以针尖偏置电压和针尖电流为参数，得到了激光脉冲产生的电离离子强度与参数之间的关系，得到了适用于不同材料的有效电离的知识，目前我们正在改进聚焦电场，寻找研制高效TOF探测器的最佳条件。研究了用针尖扫描测量方法将脱附离子的分布转化为二维图像。

项目成果

M.Yamanuki: "Thin layer electrochemical Raman study of ion pair formation between the tetrachloro-benzoquinone anion radical and alkaline earth metal cations" Journal of Electroanalytical Chemistry. 458. 191-198 (1998)

M.Yamanuki：“四氯苯醌阴离子自由基和碱土金属阳离子之间离子对形成的薄层电化学拉曼研究”电分析化学杂志。

S.Yoshida: "Dynamic Transformation in Morphology of Pd-deposited Si(111)Surface with Thermal Treatment by Using UHV-STM" Surface Sicence. 393. L87-L87 (1998)

S.Yoshida：“使用 UHV-STM 进行热处理的 Pd 沉积 Si(111) 表面形态的动态转变”表面科学。

S.Okazaki: "Correlation between the Redox potentials of 9-Substituted Anthrathense and the Results of PM3 Calculation" Electroanalysis. 9・16. 1242-1246 (1997)

S.Okazaki：“9-取代蒽醌的氧化还原电位与 PM3 计算结果的相关性”电分析 9・16（1997）。

M.Oyama: "Mechanistic Aspects of Electrochemical Reduction of 7,7,8,8-Tetracyanoquinodimethane in the Presence of Mg^<2+> or Ba^<2+>" Journal of Physical Chemistry B. 102. 6588-6595 (1998)

M.Oyama：“Mg^<2> 或 Ba^<2> 存在下 7,7,8,8-四氰基醌二甲烷电化学还原的机理”物理化学杂志 B. 102. 6588-6595 (1998)

M.Oyama: "Two dimensional CCD detection for electrogenerated chemiluminescence(ECL)on the elect〓 surface. ECL reactions concerning the microcrystals of perylene dimer cation radical salt" Journal of Electroanalytical Chemistry. (印刷中).

M. Oyama：“电子表面上电致化学发光 (ECL) 的二维 CCD 检测。有关苝二聚体阳离子自由基盐微晶的 ECL 反应”《电分析化学杂志》（出版中）。