Fig. 1. Calculated frequency shifts of different resonant modes as functions of exciting voltage

Fig. 2. Experimental setup and measurement principle. (a) Test system for SiN film mechanical oscillator frequency response; (b) reflection spectrum of FP interferometer and position of probe laser wavelength; (c) schematic of FP interferometer based on optical fiber and SiN film (inset is image of SiN film)

Fig. 3. Resonant modes of SiN film mechanical oscillator. (a) Fundamental mode (1,1); (b) high order mode (1,2) (inset is simulated mode shapes of corresponding resonant modes by finite element simulation )

Fig. 4. Effect of high-frequency nonharmonic excitation on resonant frequencies. (a) Frequency shifts of f₁₁ with and without excitation voltage of 0.1 V; (b) frequency shifts of resonance frequencies f11 andf12 under different excitation voltages

Fig. 5. Slow frequency shift of resonance frequency of SiN film mechanical oscillator as a function of high-frequency nonresonant voltage