ATOM MAMIPULATION AND EVALUATION OF PROBING TIPS

利用场发射显微镜、场离子显微镜和扫描隧道显微镜等高分辨率显微镜来阐明电子隧穿的机制是本研究重点领域的主要内容。用扫描隧道谱(STS)和场发射电子能谱(FECS)研究了表面的电子态。然而，人们已经意识到STM扫描针尖的表面原子和尖端原子之间的隧道几率随着尖端的电子态和原子排列的不同而变化。因此，这一研究部门的主要目标是用原子探针(AP)对针尖尖端的成分分布进行原子水平检测，并用FIM和STM研究原子操纵的机理。研究结果如下：(1)建立了可引入成像板(IP)的有限元/FIM模型，对隧道几率进行了定量研究。(2)研制了扫描原子探针(SAP)，用于对二维样品表面进行质量分析。对人造金刚石的质量分析进行了质量分析。(3)构造了高分辨率电荷，并在4K下探测到尖端的原子和晶格振动。(4)利用原子操纵技术，通过在晶格台阶上沉积异质原子来控制半导体表面的电子态。(5)研究了酞菁类化合物的隧穿特性，考察了它们与衬底的结合状态，并测量了I-V曲线。(6)用STM/STS研究了GaP/InP短周期超晶格中形成的自组织量子点结构。

The main subjects of this research on priority areas are the clarification of tunneling mechanism of electrons tunneling utilizing various high resolution microscoppies such as field emission microscopy (FEM), field ion microscopy (FIM) and scanning tunneling microscopy (STM). The electronic states of surfaces are investigated by scanning tunneling spectroscopy (STS) and field emission electron spectroscopy (FEES). However, it has been realized that the tunneling probability between a surface atom and an apex atom of a scanning tip of STM varies with the electronic state and atomic arrangement of the apex. Accordingly, the major aim of this research division is atomic level inspection of the constituent distributions of tip apexes with an atom probe (AP) and of electronic state with FEES and STS.The mechanism of atom manipulation is also studied FIM and STM.Results of this research are listed below.(1) The FEM/FIM which can introduce imaging plates (IP) was constructed in order to investigate the tunneling probability quantitatively.(2) A scanning atom probe (SAP) was developed to mass analyze 2-dimensional specimen surfaces. The mass analysis of artificially made diamond was mass analyzed.(3) High resolution FEES was constructed and detected the atomic and lattice vibrations at the tip apex were detected at 4K.(4) The electronic states of semicondutor surfaces were controlled by depositing foreign atoms to lattice steps utilizing atom manipulation technique.(5) Tunneling characteristics of phtalocyanines was investigated examining the binding state with the substrate and measuring I-V curves.(6) Self-organized quantum dot structures formed in GaP/InP short period superlattices were investigated by STM/STS.