【作者】 赵贵；

【导师】 孔德义；

【作者基本信息】 中国科学技术大学 ， 微电子与固体电子学， 2011， 硕士

【摘要】 信息获取技术尤其是获取微纳结构互相套准的物理特性和化学信息对于探索微观世界的奥秘具有十分重要的意义,本文在比较了国内外有关原位准同步检测材料微纳结构物化特性的方法后,介绍了一种基于原子力显微镜和高场不对称波形离子迁移谱联用(即AFM-FAIMS技术)的方案:当AFM扫描到样品表面异常的物理图像后,需要进一步获取该“兴趣点”上的化学信息时,可利用AFM探针产生电晕放电,使该“兴趣点”上的痕量化学物质脱附并离化为带电的解吸附样品离子,这些样品离子再由微型机电接口装置带入FAIMS中进行分离和检测,从而可以获取与样品“兴趣点”上物理特性相对应的化学信息。本文针对联用系统中的关键部件—AFM探针,开展了一些有关电晕放电的初步研究,主要工作有:介绍了电晕放电的一般特性,对电晕放电的产生条件、起晕电压和超始场强作了一些讨论,并且进行了3mm间距的针板式电晕放电试验,发现它与理论模型吻合得较好。简单介绍了AFM探针以及有限元方法和ANSYS软件,利用ANSYS有限元软件对AFM探针进行了静力学分析、模态仿真和电场分析,其中电场分析表明当放电间距为100um加1kv的高电压时AFM探针针尖周围的场强分布在0.32v/um至62.4v/um之间,从理论仿真的角度验证了利用其产生电晕放电的可行性。利用AFM导电探针进行了电晕放电试验,观察了实验现象,测得了AFM探针加高压时的伏安特性曲线,总结了试验规律,为下一步利用AFM探针产生电晕放电实现非触式采样奠定了良好的基础,然后还利用MEMS工艺制作可用于放电的硅尖阵列,最后介绍了一种新型的AFM探针结构并利用ANSYS对其电学特性进行了仿真。更多还原

【Abstract】 Information acquisition of physical and chemical characteristics under the micro and nano scale would be very important for exploring the secret in the micro and nano world. After comparison of some in-situ and quasi-synchronous analysis methods of micro and nano structure material, We reported a scheme which is based on AFM-FAIMS: When interesting patterns were observed during AFM scan, a relatively high voltage was applied to the AFM probe to induce corona discharge at the point of interest. Analytes were ionized by this desorption-ionization method to charged molecules or atoms, and they were extracted to FAIMS chip by radial electric field exerted by a ring electrode at the AFM-FAIMS interface. Then FAIMS would be used to detect the analytes and validate the proposed method of in-situ physical and chemical characterization of micro and nano structure material.Some preliminary research on AFM probe based corona discharge for desorption ionization in AFM-FAIMS was put forward in this paper. The characteristics of corona discharge was introduced. The requirement , onset voltage and the onset electric intensity was also discussed. Then We did an tip-plane corona discharge experiment (d=3mm), we found that the result was in accordance with the theory. An simple introduction was given to AFM probe, FEA and ANSYS software. Through finite element analysis, research was done on the mechanical and electrical character of the AFM probe. Electrical analysis showed that the field intensity around the AFM probe tip could achieve 0.32v/um-62.4v/um when the gap distance was 100um and the applied voltage was 1000v, validating the feasibility of the sampling device. The relationship between discharge current I and applied voltage V was studied through corona discharge experiment. These works laid a foundation for developing the corona discharge non-contact sampling device based on AFM probe. Then we used MEMS technology to fabricate Si tips array for corona discharge research. A novel structure of AFM probe was introduced, and research was done on the electrical characteristic of the novel probe through ANSYS software.更多还原