Murata Manufacturing Co., Ltd.

Resonant, Inc.

Nokia Corporation

Koninklijke Philips Corporation N.v.

Julius Koskela

Viktor Plesski

Patrick J Turner

Ventsislav Yantchev

Robert B Hammond

Soumya Yandrapalli

Neal O Fenzi

Bryant Garcia

Greg Dyer

Pauli Mikael Seppinen

Balam A Willemsen

Sean McHugh

Erkki Tapani Vahala

Petri Tapani Eloranta

Shunmugavelu D Sokka

Mikael Gustafsson

John Pandelis Koulakis

Hans-Otto Scheck

Filip Iliev

Jouko Lokio

Petri Eloranta

Acoustic resonator devices and acoustic filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces. The back surface is attached to a surface of a substrate. The piezoelectric plate comprises a diaphragm spanning a cavity. A conductor pattern is formed on the front surface. The conductor pattern includes a multi-mark multi-pitch interdigital transducer (IDT), wherein fingers of the IDT are on the diaphragm.

Transversely-excited film bulk acoustic resonator with multi-mark, multi-pitch interdigital transducer

Acoustic resonators, acoustic filter devices and methods of making the same. An acoustic resonator device includes a piezoelectric layer having front and back surfaces, a high acoustic velocity layer on the back surface, and an interdigital transducer (IDT) on the front surface. The high acoustic velocity layer has a higher acoustic velocity than an acoustic velocity of the piezoelectric layer.

Acoustic resonators with high acoustic velocity layers

There is disclosed acoustic resonators and filter devices. An acoustic resonator includes a single-crystal piezoelectric plate having front and back surfaces, a portion of the piezoelectric plate forming a diaphragm. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The piezoelectric plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm.

Transversely-excited film bulk acoustic resonators

Acoustic resonator devices, filter devices, and methods of fabrication are disclosed. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces. The back surface is attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The IDT is configured to excite a primary acoustic mode in the diaphragm in response to a radio frequency signal applied to the IDT. At least a portion of an edge of the diaphragm is at an oblique angle to the fingers.

XBAR resonators with non-rectangular diaphragms

There is disclosed acoustic resonators and filter devices. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The piezoelectric plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm. The interleaved fingers comprise a first layer proximate the diaphragm, a second layer over the first layer, and a third layer over the second layer, wherein adjacent layers are different materials.

Transversely-excited film bulk acoustic resonators with three-layer electrodes

There is disclosed acoustic resonators and filter devices. An acoustic resonator device includes a piezoelectric plate, and an interdigital transducer (IDT) formed on a front surface of the piezoelectric plate. The IDT includes interleaved fingers. At least one of the interleaved fingers includes a first layer adjacent the piezoelectric plate and a second layer over the first layer, wherein a width of the first layer is constant, and wherein a width of the second layer varies along a length of the at least one interleaved finger.

Transversely-excited film bulk acoustic resonators with electrodes having a second layer of variable width

An acoustic resonator device, filter devices, and methods of making the same. An acoustic resonator device includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces, where the back surface is attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. The device further includes an interdigital transducer formed on the front surface of the piezoelectric plate, where interleaved fingers of the IDT disposed on the diaphragm are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm. The interleaved fingers include a first layer adjacent the diaphragm and a second layer over the first layer, the second layer having a narrower width than the first layer.

Transversely-excited film bulk acoustic resonators with two-layer electrodes having a narrower top layer

Acoustic resonator devices and acoustic filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces, a portion of the piezoelectric plate forming a diaphragm, and a conductor pattern on the front surface, the conductor pattern comprising an interdigital transducer (IDT), interleaved fingers of the IDT on the diaphragm. A ratio of a mark of the interleaved fingers to a pitch of the interleaved fingers is greater than or equal to 0.12 and less than or equal to 0.3. A thickness of the interleaved fingers is greater than or equal to 0.85 times a thickness of the piezoelectric plate and less than or equal to 2.5 times the thickness of the piezoelectric plate.

Transversely-excited film bulk acoustic resonator with optimized electrode thickness, mark, and pitch

Acoustic resonators, filters, and methods. An acoustic resonator includes a substrate, piezoelectric plate, and a diaphragm comprising a portion of the piezoelectric plate spanning a cavity in a substrate. An interdigital transducer (IDT) on a front surface of the piezoelectric plate includes first and second sets of interleaved interdigital transducer (IDT) fingers extending from first and second busbars respectively. The interleaved IDT fingers are on the diaphragm. Overlapping portions of the interleaved IDT fingers define an aperture of the acoustic resonator. A first dielectric strip overlaps the IDT fingers in a first margin of the aperture and extends into a first gap between the first margin and the first busbar. A second dielectric strip overlaps the IDT fingers in a second margin of the aperture and extends into a second gap between the second margin and the second busbar.

Transversely-excited film bulk acoustic resonator with oxide strip acoustic confinement structures

Acoustic resonator devices and acoustic filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces. A portion of the back surface is attached to a substrate. The piezoelectric plate comprises a diaphragm spanning a cavity. A conductor pattern is formed on the front surface. The conductor pattern includes a multi-mark interdigital transducer (IDT), with fingers of the IDT on the diaphragm.

Transversely-excited film bulk acoustic resonator with multi-mark interdigital transducer

Acoustic resonators and filter devices, and methods of making acoustic resonators and filter devices. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface with interleaved fingers of the IDT on the diaphragm. The plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm. The fingers include a first layer proximate the diaphragm, and a second layer over the first layer. The first and second layers are different metals. A transverse acoustic impedance of the second layer is higher than a transverse acoustic impedance of the first layer.

Transversely-excited film bulk acoustic resonators with two-layer electrodes

Acoustic resonators and filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces, a portion of the piezoelectric plate forming a diaphragm, a conductor pattern on the front surface, the conductor pattern including an interdigital transducer (IDT), fingers of the IDT on the diaphragm, and a front-side dielectric layer on the front surface of the piezoelectric plate between the interleaved fingers. A resonant frequency is determined, in part, by a thickness of the front-side dielectric layer. A ratio of a mark of the interleaved fingers to a pitch of the interleaved fingers is greater than or equal to 0.12 and less than or equal to 0.3.

Transversely-excited film bulk acoustic resonator with a front-side dielectric layer and optimized pitch and mark

Acoustic resonators and filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces, a portion of the piezoelectric plate forming a diaphragm, and a conductor pattern on the front surface, the conductor pattern including a multi-mark interdigital transducer (IDT), with fingers of the IDT on the diaphragm. A thickness of the interleaved fingers is greater than or equal to 0.85 times a thickness of the piezoelectric plate and less than or equal to 2.5 times the thickness of the piezoelectric plate.

Transversely-excited film bulk acoustic resonator with multi-mark electrodes and optimized electrode thickness

Acoustic resonators and filter devices, and method of making acoustic resonators and filter devices. An acoustic resonator includes a substrate having a surface and a piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The interleaved fingers have an irregular hexagon cross-sectional shape.

Transversely-excited film bulk acoustic resonators with electrodes having irregular hexagon cross-sectional shapes

There are disclosed acoustic resonators, filter devices, and methods of fabricating acoustic resonators and filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces, the back surface attached to a surface of a substrate except for portions of the piezoelectric plate forming a diaphragm spanning a cavity in the substrate. A conductor pattern on the front surface includes an interdigital transducer (IDT) with interleaved fingers of the IDT disposed on the diaphragm. A plurality of holes is in the diaphragm, wherein each of the plurality of holes is configured to scatter spurious modes in the diaphragm.

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Helsinki, Finland

Julius Koskela