Increasing the Image Contrast of Atomic Force Microscope by Using Improved Rectangular Micro Cantilever

Abstract:

The resonant frequency of flexural vibrations for an atomic force microscope (AFM) cantilever has been investigated using the Euler-Bernoulli beam theory. The results show that for flexural vibration the frequency is sensitive to the contact position, the first frequency is sensitive only to the lower contact stiffness, but high order modes are sensitive in a larger range of contact stiffness. By increasing the height H, for a limited range of contact stiffness the sensitivity to the contact stiffness increases. This sensitivity controls the image contrast, or image quality. Furthermore, by increasing the angle between the cantilever and sample surface, the frequency decreases.

• Periodical: Applied Mechanics and Materials (Volumes 110-116)
• Pages: 4888-4892
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.110-116.4888
• Online since: October 2011
• Authors: Ali Sadeghi
• Keywords: Atomic Force Microscope (AFM), Flexural Vibration, Rectangular Cantilever

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[7] Timoshenko S P and Goodier J N, Theory of Elasticity , McGraw- Hill, New York , 1951: Figure1. Schematic of a rectangular AFM cantilever. The interaction with the surface is modeled by normal and horizontal springs. Figure2. Relation between the frequency and contact position for the first four modes for an AFM rectangular cantilever for Figure3. Relation between the frequency and contact stiffness for the first four modes for an AFM rectangular cantilever at various angle a for Figure4. Relation between the frequency and contact stiffness for the first four modes for an AFM rectangular cantilever at various Timoshenko beam parameter with solid line for and dashed line for Figure5. Relation between the frequency and contact stiffness for the first four modes for an AFM rectangular cantilever at various H for.

DOI: 10.1016/s0304-3991(00)00084-x