An Efficient At-Cut Quartz Crystal Resonator Design Tool For Activity Dip In Working Temperature Range

The work of an efficient design tool for engineers to enhance the frequency stability performance of AT-cut quartz crystal resonator in whole working temperature range is presented. Based on Mindlin's 2D AT-cut plate model, the design tool is a finite element analysis(FEA) program to simulate quartz plate vibration with partial electrodes(mass loading), finite dimensions(free edge), piezoelectric and temperature effects. The simulation and experiment results, including mode chart, electrical response and frequency-temperature characteristics, of a 3.2mm by 2.5mm 40MHz resonator are shown in this study. Finally, an activity-dip-contour-map which locates the high frequency-temperature stability zone is constructed and it guides engineers to do a robust design.