Investigation of dynamics of cantilever-type microstructure by laser Doppler vibrometry

Abstract

Electrostatic surface-micromachined microswitch and initial results of investigation of its dynamics by laser Doppler vibrometry (LDV) technique is presented in the paper. It is demonstrated that the present LDV-based measurement set-up is able of registering only the vibrations of substrate on which the microswitches are fabricated. Due to submillimeter-scale dimensions and submicrometer-scale vibration amplitudes as well as associated high natural frequencies of the cantilever structures of the microswitch the measurement setup is not suitable for experimental research of their dynamic characteristics. Based on these observations, major set-up improvements were suggested. They are connected with diminishing laser beam spot area and increasing resolution of the laser Doppler vibrometer as well as range of detectable and excitation vibration frequencies.