| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a low-cost and miniaturized piezoelectric thin-film resonator and its manufacturing method having superior characteristics, and which is readily manufactured, and having a high yield. <P>SOLUTION: The present invention relates to a piezoelectric thin-film resonator 1A, having a piezoelectric thin film 12 formed on a first side of a substrate 11, and a lower electrode 13 and an upper electrode 14, formed so as to hold the piezoelectric thin film 14 therebetween. The piezoelectric thin film 12 is formed from aluminum nitride, and the upper electrode 14 and the lower electrode 13 include a layer of ruthenium or ruthenium alloy, respectively. In the lower electrode 13, a thin-film layer 16 is formed of a material which is softer than the lower electrode, while being exposed as a whole in an air gap 15 formed under the lower electrode. <P>COPYRIGHT: (C)2011,JPO&INPIT |
