An acoustic resonator comprises a first electrode a second electrode and a piezoelectric layer disposed between the first and second electrodes. The acoustic resonator further comprises a reflective element disposed beneath the first electrode, the second electrode and the piezoelectric layer. An overlap of the reflective element, the first electrode, the second electrode and the piezoelectric layer comprises an active area of the acoustic resonator. The acoustic resonator also comprises a bridge adjacent to a termination of the active area of the acoustic resonator.

Acoustic resonator structure comprising a bridge

An acoustic wave device includes: a piezoelectric film made of an aluminum nitride film containing a divalent element and a tetravalent element, or a divalent element and a pentavalent element; and an electrode that excites an acoustic wave propagating through the piezoelectric film.

Acoustic wave device

An acoustic resonator comprises a first electrode and second electrode comprising a plurality of sides. At least one of the sides of the second electrode comprises a cantilevered portion. A piezoelectric layer is disposed between the first and second electrodes. An electrical filter comprises an acoustic resonator.

Acoustic resonator structure having an electrode with a cantilevered portion

A piezoelectric thin film resonator includes: a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode located to sandwich the piezoelectric film; a load film formed from patterns in a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, wherein the patterns are formed so as to surround a center of the resonance region and intersect with a pathway extending from the center to an outer periphery of the resonance region.

Piezoelectric thin-film resonator and filter

In an elastic wave device, an electrode, which is formed in a comb-like shape and is made of conductive material having a prescribed thickness, is arranged on a substrate of a piezo-electric element containing lithium niobate as a main component Also, in this elastic wave device, a surface of the substrate is set to a plane which is obtained by rotating a plane perpendicular to a crystal Y-axis of the lithium niobate by an angle ranging from 55 degrees to 57 degrees around a crystal x-axis of the lithium niobate, and a duty ratio (a width w of an electrode finger/an arrangement interval p of a pair of electrode fingers) of each of a plurality of electrode fingers composing the electrode is equal to or higher than 04 and is lower than 10

Elastic wave device

A piezoelectric thin film resonator includes a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and an upper electrode formed on the piezoelectric film, the lower electrode and the upper electrode opposing each other through the piezoelectric film to form an opposing region, the opposing region including a space at a boundary of the opposing region. The space extends from an innerside to an outer side of the opposing region and is formed in or on the piezoelectric film.

Piezoelectric thin0film resonator, filter using the same, and duplexer using the same

PROBLEM TO BE SOLVED: To provide a filter and a demultiplexer capable of reducing ripple produced in a pass band. SOLUTION: The filter and the demultiplexer includes a plurality of piezoelectric thin film resonators each consisting of a substrate (10), a lower electrode (12) provided on the substrate, a piezoelectric film (14) provided on the lower electrode, and an upper electrode (16) provided on the piezoelectric film. At least one piezoelectric thin film resonator among the plurality of the piezoelectric thin film resonators is configured, in a way that a shape thereof at a portion where the lower electrode and the upper electrode face each other sandwiching the piezoelectric film therebetween is different, in view of spurious generation frequency from that of other piezoelectric thin film resonator. COPYRIGHT: (C)2008,JPO&INPIT

Filter and demultiplexer

PROBLEM TO BE SOLVED: To provide a piezoelectric membrane resonator suitable for miniaturization and having superior resonance characteristics, a filter composed thereof and a production method for such a piezoelectric membrane resonator. SOLUTION: The piezoelectric membrane resonator 100 is provided with a substrate 110 having a first surface 111 and a second surface 112 opposed thereto and a laminated resonant body 120 composed of a first electrode film 121 in contact with the first surface 111, a piezoelectric film 123 overlapped on the relevant first electrode film 121 and a second electrode film 122 overlapped on the relevant piezoelectric film 123 and on the substrate 110, at a position corresponding to the laminated resonant body 120, a cavity 110a approximately vertical to the first surface 111 is opened while having a first opening 111a opened on the first surface 111 and a second opening 112a opened on the second surface 112. COPYRIGHT: (C)2003,JPO

Piezoelectric membrane resonator, filter and production method for piezoelectric membrane resonator

PROBLEM TO BE SOLVED: To provide a piezoelectric thin film vibrator with small characteristic variation and a filter using it by suppressing bad influence of a lateral mode wave, adopting a structure with sufficient strength of a membrane part and manufacturing nature of a good air gap. SOLUTION: In a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and a piezoelectric thin film vibrator including the upper electrode formed on the piezoelectric film, a shape of a part facing the upper electrode and the lower electrode is elliptic, and when length of the main axis of the elliptic form is a, and length of the sub-axis is b, the vibrator is composed to satisfy 1<a/b<1.9. COPYRIGHT: (C)2005,JPO&NCIPI

Piezoelectric thin film vibrator and filter

PROBLEM TO BE SOLVED: To reduce resistance of a metal layer which can also be used as a wiring for connecting piezoelectric thin-film resonators or between a piezoelectric resonator and a pad electrode. SOLUTION: The piezoelectric thin-film resonator has a first metal layer (48a) and a second metal layer (48b) provided on a substrate (41); a lower electrode (43) provided on the first metal layer (48a) so as to be electrically connected to the first metal layer (48a), to extend from the first metal layer (48a) toward the second metal layer (48b) and to form a gap (46) between itself and the substrate (41); a piezoelectric film (44) provided on the lower electrode (43); and an upper electrode (45) provided on the piezoelectric film (44) and electrically connected to the second metal layer (48b). The filter and the manufacturing method thereof are also provided. COPYRIGHT: (C)2007,JPO&INPIT

Takeshi Yokoyama

Papers

Piezoelectric thin0film resonator, filter using the same, and duplexer using the same

Filter and demultiplexer

Piezoelectric membrane resonator, filter and production method for piezoelectric membrane resonator

Piezoelectric thin film vibrator and filter

Piezoelectric thin-film resonator, filter, and method of manufacturing the piezoelectric thin-film resonator