| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface acoustic wave device having excellent temperature characteristics and a sufficient electromechanical coupling coefficient. <P>SOLUTION: The surface acoustic wave device 1 includes a sapphire substrate 10 having a C-plane as a main surface 11, comb-like electrodes 21, 22 formed in contact with the main surface 11 of the sapphire substrate 10, an aluminum nitride film 30 for covering the comb-like electrodes 21, 22, and a silicon dioxide film 40 formed on the surface of the aluminum nitride film 30. The surface acoustic wave device 1 has the excellent temperature characteristics, the sufficient electromechanical coupling coefficient necessary for oscillation, and a high acoustic velocity by setting the proper range of relation between the standardized film thickness KH-AlN of the aluminum nitride film 30 and the standardized film thickness KH-SiO<SB>2</SB>of the silicon dioxide film 40. <P>COPYRIGHT: (C)2011,JPO&INPIT |
