Magnetomotive and Tension-Based Tuning of a Micromechanical Resonator

Bidirectional frequency tuning in microresonators is demonstrated through the simultaneous use of both mechanical (stretching) and magnetomotive approaches. Stretching is employed to increase the resonance frequency, while the magnetomotive method provides actuation and spring softening. The fabrication process is presented for a double-clamped micromechanical nickel resonator. Lorentz Force is used for excitation and flexural deformation of the resonator. A substrate bending method is utilized to introduce uniaxial tension in the resonator. As a result of flexural deformation, up to 13% decrease in the resonance frequency is achieved. An 8% increase in the resonance frequency is obtained by the stretching method. The presented study is the first demonstration of the combination of the aforementioned techniques for the bidirectional and wide-range frequency tuning up to 200 kHz.