Nano-machining and Mechanical Testing of Nano-materials inside a Scanning Electron Microscope

• Main Authors: Shen-Chia Li, 李伸家
• Other Authors: Ming Chang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/61623446429056159810

碩士 === 中原大學 === 機械工程研究所 === 95 === The present investigation describes about the applications of a four degrees of nano-manipulator system for three-dimensional nano-machining and nanomechanical characterization of nanoscale objects inside a scanning electron microscope (SEM). The nanomanipulation system consists of precisely machined platform, picomotors and monolithic-silicon-based tips which are generally used in atomic-force microscopes (AFM). The manipulator system is used for two different applications, (i) Nano machining of gold coated silicon substrate (ii) Nanomechanical characterization of TiO2 nanowires (NWs) In nano-machining, the AFM tip is used to pattern nano-materials such as gold (Au) coating on silicon. Image feedback control method is used for precise machining and the processed results are determined with AFM. Molecular dynamics simulation method is used to analyze the experimental results by considering different parameters such as cutting speed and volume remove for different cutting depth etc. Hence nano machining with the manipulator can produce nano-lines, readable nano-scale words and micro channels. Moreover, it can also chuck out the removed material from the sample surface. The manipulator system is used to determine the elasticity co-efficient NWs by employing compression experiment. NWs are synthesized by microwave hydrothermal method. The electron beam induced deposition (EBID) method is used to clamp NWs to the AFM tips attached to the nanomanipulator platform inside the SEM vacuum chamber. The buckling instability of the NWs is studied by applying continuously increasing load on it and analyzed from a series of SEM image. The Young’s modulus of the NWs is determined using Euler buckling model. To measure the cross sectional area of the NWs, aluminum is coated on NWs to improve resolution of SEM images. The Young’s modulus of the NWs has been measured to be 16.31±1.05GPa.