| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain characteristics of an incommensurablly wide band by providing a metal thin film as an epitaxial film on an Si substrate and forming a PZT thin film, which is epitaxial in 90 deg. domain structure wherein (100) orientation and (001) orientation are mixed at a specific atomic ratio Ti/(Ti+Zr), on it. SOLUTION: On the Si substrate 2 in which a via hole 1 is formed, a buffer layer 3, a base electrode 4 formed of Pt, a PZT thin film 5, and an upper electrode 6 made of Au are provided in this order. This PZT thin film 5 has a 0.65 to 0.90 of atomic ratio Ti/(Ti+Zr) and is a 90 deg. domain structure epitaxial film where (100) orientation and (001) orientation are mixed. Further, the base electrode 4 is a (001)-orientation epitaxial film, the reverse surface of the Si substrate 2 is adhered to the bottom surface of a package 11 with a die-bonding agent 10, and the upper part of the package 11 is sealed with a lid 13. Consequently, the constituted thin film bulk wave resonator obtains superior piezoelectric characteristics without polarizing processing the PZT film 5.</p> |
