Resonance Characteristics of Micro Cantilever in Liquid

The resonance characteristics of a micro cantilever are experimentally and theoretically studied. The micro cantilever is vibrated by thermal excitation using laser exposure and the frequency responses of the micro cantilever in air, acetone and water are experimentally evaluated based on an optical measurement technique. It is demonstrated that the resonance frequencies in water decrease to about one-tenth of the values in air. Also, the frequency responses are calculated using the string of beads model taking into consideration the drag force by viscous fluids. The calculation results show good agreement with the experimental results.