| 摘要 |
PURPOSE:To improve temperature characteristics, to increase a Q factor, and to lower a subordinate resonance level by sticking an Al electrode, whose film thickness is >=1.5% of surface acoustic wave wavelength, to a quartz substrate which is treated by rotary Y cutting and allows a surface wave to propagate in an X-axis direction. CONSTITUTION:Busbar electrode 2 and 3 are provided on the main surface of a quartz substrate 1. An interdigital electrode consists of many opposing comb- shaped fingers 4 and 5 which are extended alternately from the electrodes 2 and 3 in parallel. The quartz substrate is treated by rotary Y cutting, and a surface wave propagates in the X-axis direction. Further, the interdigital electrode uses Al and its film thickness is >=1.5% of the wavelength of the surface acoustic wave. As a result, a sufficiently large Q factor is obtained without increasing the number N of couples of electrode fingers, and while temperature characteristics are improved, a subordinate resonance level is lowered. |
