A design and fabrication method for a silicon micromachined resonant accelerometer based on a zinc oxide (ZnO) nanowire is reported. The key and sensitive element of the accelerometer is a nanowire-based resonator with a single ZnO nanowire suspended across two micromachined Cr/Au electrodes. A dielectrophoresis technique is used to assemble the ZnO nanowire onto electrodes
then a Focused Ion Beam (FIB) is employed to deposit Pt on the contact between the nanowire and electrodes to clamp the nanowire and eliminate the Schottky barriers at the interfaces. When an external acceleration is applied
the inertial force generated by the proof mass imposes a stress on the nanowire through the beams that support the suspended proof mass. Consequently
the acceleration is associated with the shift in the resonant frequency of the nanowire. By its quasi-digital output
the trouble in detecting feeble analog signals from most MEMS devices could be averted. Experimental results show that the sensitivity of the accelerometer increases dramatically with the decrease of the nanowire's thickness. In the design
nanowire with a thickness of 500 nm is selected for the theoretical analysis
and the sensitivity of the acceleration sensor is estimated to be more than 2.5 kHz/