奈米工程與微系統研究所　書報討論

Seminar of Inst. NanoEngineering and MicroSystems

Hideki Kawakatsu

Institute of Industrial Science, University of Tokyo

Professor

Title:

Colour Atomic Force Microscopy and Related Techniques

- Rapid Mapping of the Potential Landscape -

Abstract:

We have implemented a method to acquire effective Morse parameters on-the-fly by introducing position modulation at frequency ω around the bottom of the frequency shift curve (Bottom Tracking). It was demonstrated that atomic resolution is obtained for silicon and solder with the proposed mode. Numerical calculation from the 2ω intensity, dfDC and Z(=movement of the z piezo) gave effective Morse parameters that can curve fit the experimental frequency shift curve.

Functionalising the tip apex with a molecule is known to lessen the effect of the background force, and bring the effective Morse parameters closer to the pairwise potential. There exists an optimum value of molecular protrusion r for a given tip radius R. Based on a rough model, Ebeff/Eb was calculated for different values of molecular height d. Molecular height d of about 4 Å or larger is effective in lessening the effect of tip volume. In actual implementation, vertical and lateral stiffness of the molecule needs to be taken into consideration. In the talk, I will also be presenting related techniques and details of the instrumentation.

15:30-17:20 on Nov. 4(Mon), 2019 at Room 108 of Eng. Building I

Host：Prof. Mei-Feng Lai mflai@mx.nthu.edu.tw Ext:33998

Contact：Ming-Wei Wang cenawang0216@gmail.com