Development of Preparation Methods of SXM Tips with a Ultra-fine Probing Area

具有超精细探测区域的 SXM 探针制备方法的开发

基本信息

批准号：
02555004
负责人：
TOMITORI Masahiko
金额：
$ 5.18万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02555004/
关键词：
Scanning X Microscope (SXM)Scanning Tunneling Spectroscopy (STS)Scanning Tunneling Microscope (STM)Atom-Probe Field Ion Microscope (A-P FIM)Field Emission Electron Spectroscopy (FEES)Scanning Tip Apex 位置検出型アトムプロ-ブ原子間力顕微鏡

项目摘要

Scanning X microscope (SXM) is a generic term various scanning microscopes which can depict the topography of sample surfaces in atomic scale by tracing the surfaces with atomically sharpened tips. While scanning the surface with the tip, a tip-sample distance is maintained constant in the SXM operation mode by keeping a physical quantity constant, which is interchanged between the tip apex and the sample surface, and strongly depends on the tip-sample distance. Thus the SXM images processed from the scanning tip tracing show the surface structures with the atomic resolution. A scanning tunneling microscope (STM) is a representative of the SXM family, which utilizes the tunneling current passing between the tip apex and the sample surface. Since the tunneling current is extremely sensitive to the tip-sample distance, even if the distance changes as small as 0.1, A, the current changes remarkably, and the atom-resolved surface images can be obtained by scanning the sample surface with a … More n atomically sharpened tip at a constant tunneling current. In addition to the STM, scanning tunneling spectroscopy (STS), an atomic force microscope (AFM), and the other scanning microscopes have been developed and advanced in a short duration. By the STS the surface state density can be imaged in the atomic resolution from the tunneling current-bias voltage characteristics, and the AFM can depict the surface topography utilizing the force exerted between the tip and the sample.However, the resolution and the reliability of the SXM images depend strongly on the tip sharpness and the stability of the atomic structure. Thus the urgent development of reliable methods to prepare and evaluate SXM tips is indispensable. In this study, using the UHV-STM/STS and the atom-probe field ion microscope combined with a field emission electron spectroscopy (A-P FIM/FEES), the characteristics and availability of the SXM tips prepared by vacuum-and electro-deposition techniques were investigated. The atomic and electronic structures of electrochemically etched Ir tips covered with Ge were studied by the A-P FIM/FEES to get information on changes in the surface states and semiconductive energy gap induced by the deposited Ge. The effects of Ge atoms adsorbed on the scanning tips can be estimated from this experiment. The surface and electronic structures of a conductive polymer were also investigated by the UHV-SnVSTS. Furthermore, the tip covered. with the conductive polymer was developed to study the detailed structures of the electronic-states of the polymer. Less

扫描X显微镜（SXM）是各种扫描显微镜的总称，它可以通过用原子锋利的尖端追踪表面来在原子尺度上描绘样品表面的形貌，同时用尖端扫描表面，尖端与样品的距离保持恒定。 SXM 操作模式通过保持物理量恒定来实现，该物理量在尖端顶点和样品表面之间互换，并且强烈依赖于尖端-样品距离，因此从扫描尖端跟踪处理的 SXM 图像显示了表面结构。扫描隧道显微镜 (STM) 是 SXM 系列的代表，它利用针尖顶点和样品表面之间通过的隧道电流，因为隧道电流对针尖与样品之间的距离极其敏感。距离变化小至 0.1 A，电流变化异常，并且除了隧道电流之外，还可以通过用原子锐化尖端扫描样品表面来获得原子分辨表面图像。 STM、扫描隧道光谱 (STS)、原子力显微镜 (AFM) 和其他扫描显微镜已在短时间内得到开发和改进，通过 STS，可以根据隧道电流以原子分辨率对表面态密度进行成像。 -偏压特性，AFM可以利用针尖与样品之间强烈施加的力来描绘表面形貌。然而，SXM图像的分辨率和可靠性取决于针尖的清晰度和原子的稳定性因此，迫切需要开发可靠的方法来制备和评估 SXM 尖端，在本研究中，使用 UHV-STM/STS 和原子探针场离子显微镜与场发射电子能谱 (A-P FIM/FEES) 相结合。，研究了通过真空和电沉积技术制备的SXM尖端的特性和可用性。通过A-P研究了电化学蚀刻的Ge覆盖的Ir尖端的原子和电子结构。 FIM/FEES 以获得由沉积的 Ge 引起的表面态和半导体能隙变化的信息。吸附在扫描尖端上的 Ge 原子的影响也可以从该实验中估算出导电聚合物的表面和电子结构。此外，还开发了覆盖有导电聚合物的尖端来研究聚合物电子态的详细结构。