Interfacial heterostructure between nano apex and metal

• Main Authors: Chung-hiang Chien, 簡崇翔
• Other Authors: Chien-Cheng Kuo
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/g5je24

碩士 === 國立中山大學 === 物理學系研究所 === 106 === The target of the research is that making and observing the interfacial heterostructure on the apex of tungsten tip which is deposited metal film. To get the interfacial heterostructure, the nano-apex need to be fabricated. After that the apex will become a suitable holder by taking thermal treatment. Finally, depositing a metal layer and checking the apex is still good or not by scanning electron microscopy, and then taking it in transmission electron microscopy. The adsorbed things on the sample can be removed by plasma cleaning, and then hitting sample by electron beam to get TEM image of profile of apex. We used TEM to measure sample for two times, STEM for one times. The images were changed to reciprocal space images by fast fourior transform, then they were helpful in analyzation of difference between deposited chromium tips and none-deposited chromium tips. The conclusion in this research is that the apex which is desposited chromium and do thermal treatment still has chance to form a periodic structure.As a result, the interfacial heterostructure of the apex with chromium film is similar to (111) plane periodic structure of body-centered cubic (BCC) . However, the samples in this research are not enough, so we should consider how to improve the success rate of forming the periodic structure. Simultaneously , the thickness of metal film should be decreased to get more detailed atomic analyzation.