abstract |
A novel Si MEMS piezoresistive resonator is described. The resonator has a shape of a frame, such as a ring or a polygon frame, which has two or more anchors. Electrodes located at the outer or inner rim of the resonant structure are used to excite the structure electrostatically into resonance with a desired mode shape. One or plurality of locally doped regions on the structure is used for piezoresistive readout of the signal. In the most preferred embodiments, the structure is a ring, which has four anchors, two electrodes and four piezoresistive regions at different segments of the structure. The piezoresistive regions are alternatively located at the outer rim and inner rim of the structure in such a way that the piezoresistive signals of the same sign from different regions can be collected. Advantages of this device are large readout signal, large electrode area, robustness, suppressed out-of-plane vibration and larger usable linear range. |