| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a thin film bulk wave sound resonator capable of restraining degradation of a high-frequency characteristic. <P>SOLUTION: The thin film bulk wave sound resonator is equipped with a second insulating layer pattern 2 arranged separately from a first insulating layer pattern 1, a third insulating layer pattern 3 arranged separately from the first insulating layer pattern 1 on an opposite side of the second insulating layer pattern, and a fourth insulating layer pattern 4 arranged on the opposite side of the first insulating layer pattern separately from the second insulating layer pattern, an underneath conductive layer 40 ranging from an inside of a region surrounded by the first and second insulating patterns to an upside of the third insulating layer pattern via the first insulating layer pattern, a piezoelectric film 42 each of whose opposed outer edges is arranged on the first and second insulating layer patterns and which is arranged on a surface of the underneath conductive layer, and an upside conductive layer 48 which is opposed to the underneath conductive layer in a manner of sandwiching the piezoelectric film 42 and ranges further to an upside of the fourth insulating layer pattern via the second insulating layer pattern. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
