Research on effects of electrode material on integrated resonator force sensitive characteristic

Based on the relation of force sensitive characteristic of quartz crystal resonator with adding force azimuth and wave propagation in crystal lame, and according to the wave restrict theory of crystal vibration, the integrated three-electrode resonator is designed and fabricated on the same crystal wafer. We study the relations of the resonators with this structure the force sensitive characteristic with adding force azimuth and the electrode material and carry on experiments of comparing same-base resonators of aurum electrodes with aluminum electrodes. The results show that the resonators' force sensitive characteristic is closely related to adding force azimuth, when psi is 0deg, the force-sensitive coefficient is maximum; and the electrode materials affect the resonators' force sensitive characteristic through impacting its effective electromechanical coupling coefficient, the maximum difference between Au and Al integrated resonator is 189.8 Hz/N.

I. Introduction

There are many literature reports about applications of single electrode quartz resonator in force or stress field based on quartz crystal force sensitive characteristic [[1]~[2][3]]. When quartz crystal is under force or stress, its force-frequency conversion coefficient is related to the electrode position, electrode material and adding force azimuth of the resonator. Based on the force sensitive character of quartz crystal resonator, the integrated three-electrode resonator is designed and fabricated on the same crystal wafer, and aurum electrodes and aluminum electrodes are used respectively in the electrode area. Then we use frequency mixing processing of the output frequencies of different resonators, and test the force sensitive character of integrated resonator with relevant test equipment. The results show that in the condition of same electrode structure, the force sensitive character of the integrated quartz crystal resonator with Au electrodes is better than that with Al electrodes.