Method of extremely efficiently using materials of LBO and quartz in SAW and bulk wave resonator

The limit seems to come to ultrasonic electronics devices that control time and the frequency for the making to high performance. Therefore, it decided to review it from the essence of the piezoelectric materials. The method of making to high performance to optimize the fundamental property of lithium tetraborate (Li₂B₄O₇:LBO) and quartz used as stabilized materials for the SAW and bulk wave resonator is researched. The electromechanical coupling constant of LBO SAW is comparatively wide with 1%. The frequency shift is large and the temperature characteristic is not good though it is used as an IF filter. The in-plane anisotropy is positively used for the temperature change´s improvement. The SAW chip does die bonding through the buffer layer. The temperature characteristic was found 1:4 or more being able to do the aspect ratio of the chip with 45°X-cut plate, and to be being improved at the ST-cut level. The method of exciting the space of LST-cut can exclude various influences that the mass loading has on the leaky SAW property. This spatial excitation is examined about the optimum structure of the LST-cut SAW resonator that has third-order temperature coefficient. As the method of realizing high-Q bulk wave resonator near material Q of quartz, the lens processing of quartz is the only solution. The influence given to the temperature characteristic after the lens of double rotated SC-cut plate is processed and the Q-factor that can be realized are investigated.