发明名称 |
Piezoelectric resonator, method of manufacturing piezoelectric resonator, and filter, duplexer, and communication device using piezoelectric resonator |
摘要 |
A piezoeletric resonator includes: a substrate; a lower electrode formed on or above the substrate; a piezoeletric body formed on or above the lower electrode; an upper electrode formed on or above the piezoeletric body; and a cavity under a vibrating portion formed by the lower electrode, the piezoeletric body, and the upper electrode. Where a resonant frequency of vibration with a thickness of the vibrating portion being a half of a wavelength is taken as fr, an average of ultrasonic velocity in a material forming the cavity is taken as Vc, and a value determined based on the resonant frequency fr and the average of ultrasonic velocity Vc is taken as lambdac (=Vc/fr), a depth of the cavity is set so as to be equal to or larger than nxlambdac/2-lambdac/8 and equal to or smaller than nxlambdac/2+lambdac/8.
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申请公布号 |
US2007001781(A1) |
申请公布日期 |
2007.01.04 |
申请号 |
US20060488148 |
申请日期 |
2006.07.18 |
申请人 |
NAKATSUKA HIROSHI;ONISHI KEIJI;NAKAMURA HIROYUKI;YAMAKAWA TAKEHIKO;YAMAGUCHI HIROSHI |
发明人 |
NAKATSUKA HIROSHI;ONISHI KEIJI;NAKAMURA HIROYUKI;YAMAKAWA TAKEHIKO;YAMAGUCHI HIROSHI |
分类号 |
H03H9/70;H03H3/04;H03H9/02;H03H9/17;H03H9/54;H03H9/56 |
主分类号 |
H03H9/70 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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