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Combining the energy limit theory and the ANSYS finite element simulation analysis, this paper has designed the new integrated quartz crystal resonator and has used oscillator circuits to carry on the experimental comparison on its temperature-frequency characteristic in high-low temperature chamber. The experimental results show that the curve of its temperature-frequency characteristic is cubic in the coordinate system, which is basically consistent with that of the single electrode resonator. The frequency change of each resonator on the same substrate is basically the same when they are in the same circumstance and stimulation. According these similarities, this paper can implement differential processing on output frequencies of different resonators on the same substrate, which can effectively restrain the influence that temperature imposes on frequency.

By analysing the wafer, the electrodes, etc. according to the energy limit theory and the ANSYS finite element simulation, in this paper the author has designed the integrated quartz crystal resonator and oscillator circuit, and has carried on the experimental comparison on the stability of the integrated resonators, which have different structure, different electrode material and thickness. The experimental results show that the frequency stability of quartz crystal resonator is not only related with the electrode material and thickness, but also related with the structure. Under the same condition, resonator of asymmetric structure has better frequency stability, and the stability of Au-electrode was better than others, and its magnitude could reach 10 10. With the increase of the electrode thickness, the resonator oscillator stability will be improved.

Analyzing stress distribution of the thin circular quartz wafer subjected the radial force through the ANSYS finite element simulation, as well as the theoretical simulation, this paper designed two integrated quartz resonators with different structures and carried on experiments on force-frequency characteristic of resonators. The experimental results show that the resonators force-frequency characteristic is not only closely related to adding force azimuth, but also the electrode size and position. And when force azimuths are same, integrated resonator with asymmetric structure has better force-frequency characteristic, its force-frequency conversion coefficient could achieve 551.8Hz/N after electrode was evaporated with Au.

According to the oscillation characteristics of the quartz crystal resonator and the relationship between its force sensitive property and stress distribution on crystal plate, the single-base multiple-electrode quartz crystal resonator is designed. The oscillation stability of the resonator with this structure is tested by using crystal frequency stability tester. The force-frequency property of the resonators formed by electrodes on different positions of the new structure crystal plate is studied by adding radial force on it. The experimental results show that when the new structure quartz crystal resonator works driven by integrated chip, its oscillation frequency stability can reach 10-8, with the electrode thickness increasing, the oscillation stability of the resonators improves. The force-frequency property of the resonator on the different position of the same crystal plate is different, and the force-frequency coefficient has an obvious difference. The total force-frequency coefficient of the newly designed single-base three-electrode quartz crystal resonator can reach 338.8Hz/N by using mix frequency process.

According to the stress distribution in the thin round-shaped quartz plate with radial force, multiple resonators are designed in the different positions on same quartz crystal wafer. The force sensitive property of the resonators in different positions is studied. The research result shows, the force sensitive property of the resonator is closely related to the locations and the adding force azimuth; the force sensitive property of the resonators in different positions have a significant difference. If making difference frequency process of the resonant frequencies which is produced by the resonators, the interfering factors of the temperature etc. can be inhibited; if making superposition and integration process of the resonators’ force sensitive property, the total force sensitive property of the resonator with the multiple-electrode structure can be improved.

According to the characteristics of force-frequency character of quartz crystal and a kind of structure of mono-base multi-electrode quartz resonator, a new signal processing scheme is presented. Base frequency signals are firstly outputted when different places resonator is vibrated synchronously, and then are sent to mixer, after difference frequency signals are obtained, signals are sent to mixer again, sum frequency signals are obtained through high-pass filter. At last, multiple frequency signals are outputted. Force sensitive experiments are performed by using the new scheme, and the results are analyzed. The results show that the new scheme is valid and effective, and the new circuits can inhibit interference factors that temperature induced, and to maximize to obtain a valid signal of the quartz crystal resonator. At the same time, force sensitive coefficients are optimized. Precision can be improved when this circuit design scheme is used in the corresponding sensor design.