Avago Technologies General IP (singapore) Pte. Ltd.

Avago Technologies International Sales Pte. Limited

Avago Technologies Wireless IP (singapore) Pte. Ltd.

Agilent Technologies, Inc.

John Choy

Phil Nikkel

Kevin J Grannen

Chris Feng

Dariusz Burak

David Martin

Tina L Lamers

Alexandre Shirakawa

Joel Philliber

Qiang Zou

Carrie A Rogers

Donald Lee

Tangshiun Yeh

John Dwight Larson, Iii

Osvaldo Buccafusca

Stefan Bader

Ivan Ionash

Paul D Bradley

Hongjun Feng

Urupattur C Sridharan

Kristina Lamers

Steve Gilbert

Vikram Patil

Sook Ching Chang

Tom Yeh

A bulk acoustic wave (BAW) resonator includes a substrate defining a cavity, a bottom electrode disposed over the substrate and the cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer. The piezoelectric layer includes polycrystalline lithium niobate (LN) material or polycrystalline lithium tantalite (LT) material. The BAW resonator may further include an encapsulant layer formed on side and top surfaces of the piezoelectric layer. The encapsulant layer is configured to protect the LN material or the LT material of the piezoelectric layer from a release solvent previously applied to sacrificial material within the cavity in the substrate.

Bulk acoustic wave resonator with piezoelectric layer comprising lithium niobate or lithium tantalate

An acoustic resonator is disclosed. The acoustic resonator comprises a substrate, a first electrode, a second electrode and a piezoelectric layer positioned between the first electrode and the second electrode. An acoustic reflector is positioned between the first electrode and the substrate. An active area comprises a region of contacting overlap of the acoustic reflector, the first electrode, the piezoelectric layer and the second electrode. A gap region extends around the active area.

Acoustic resonator structure having an electrode with a cantilevered portion

A bulk acoustic wave (BAW) resonator includes: a substrate; an acoustic reflector disposed in the substrate; a first electrode disposed over the acoustic reflector; a second electrode; and a piezoelectric layer between the first and second electrodes. The second electrode is not disposed between the first electrode and the acoustic reflector. The BAW resonator further includes a block disposed over the substrate and beneath the piezoelectric layer. A contacting overlap of the acoustic reflector, the first electrode, the second electrode and the piezoelectric layer defines an active area of the BAW resonator.

Bulk acoustic wave resonator

An acoustic resonator device includes a composite first electrode disposed over a substrate; a piezoelectric layer disposed on the composite first electrode, the piezoelectric layer including a piezoelectric material doped with scandium for improving piezoelectric properties; and a second electrode disposed on the piezoelectric layer. The composite first electrode includes a base electrode layer disposed over the substrate; a temperature compensation layer disposed on the base electrode layer; a seed interlayer disposed on the temperature compensation layer, the seed interlayer having a thickness between about 5&#x212b; and about 150&#x212b;; and a conductive interposer layer disposed on at least the seed interlayer, at least a portion of the conductive interposer layer contacting the base electrode layer. The piezoelectric layer has a negative temperature coefficient and the temperature compensation layer has a positive temperature coefficient at least partially offsetting the negative temperature coefficient.

Temperature compensated acoustic resonator device having thin seed interlayer

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. A bridge disposed adjacent to one of the sides of the second electrode.

A method is provided for forming a piezoelectric layer during a corresponding deposition sequence. The method includes sputtering aluminum nitride onto a sputtering substrate inside a reaction chamber having a gas atmosphere, the gas atmosphere initially including nitrogen gas and an inert gas, causing growth of the piezoelectric layer with a polarity in a negative direction. The method further includes adding a predetermined amount of oxygen containing gas to the gas atmosphere over a predetermined period of time, while continuing the sputtering of the aluminum nitride onto the sputtering substrate during a remainder of the deposition sequence, such that the piezoelectric layer is monolithic. The predetermined amount of oxygen containing gas causes the polarity of the aluminum nitride piezoelectric layer to invert from the negative direction to a positive direction, opposite the negative direction.

Acoustic resonator including monolithic piezoelectric layer having opposite polarities

A bulk acoustic wave (BAW) resonator device includes a bottom electrode on a substrate over one of a cavity and an acoustic mirror, a piezoelectric layer on the bottom electrode, a top electrode on the piezoelectric layer, and a temperature compensation feature having positive temperature coefficient for offsetting at least a portion of a negative temperature coefficient of the piezoelectric layer. At least one of the bottom electrode and the top electrode includes an integrated lateral feature configured to create at least one of a cut-off frequency mismatch and an acoustic impedance mismatch.

Acoustic resonator having integrated lateral feature and temperature compensation feature

A bulk acoustic wave (BAW) resonator having a first electrode, a second electrode, and a piezoelectric layer between the first electrode and the second electrode. The first electrode is of a first electrode material. The second electrode is of a second electrode material. The piezoelectric layer is of a piezoelectric material doped with at least one rare earth element. The BAW resonator has a resonant frequency dependent at least in part on respective thicknesses and materials of the first electrode, the second electrode and the piezoelectric layer. The resonant frequency has a temperature coefficient. At least one of the first electrode and the second electrode includes a niobium alloy electrode material that, relative to molybdenum as the electrode material, reduces the temperature coefficient of the resonant frequency of the BAW resonator.

Bulk acoustic wave devices with temperature-compensating niobium alloy electrodes

An acoustic resonator device includes a bottom electrode disposed on a substrate over an air cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer, where an overlap between the top electrode, the piezoelectric layer and the bottom electrode over the air cavity defines a main membrane region. The acoustic resonator device further includes at least one metal frame disposed on a bottom surface of the bottom electrode having a thickness that ranges from about 10% to about 75% of a thickness of the bottom electrode in a central region of the bottom electrode. The thickness of the metal frame improves heat dissipation out of the acoustic resonator device while also improving structural stability of the acoustic resonator device without detrimentally affecting its performance.

Acoustic resonator device with at least one air-ring and frame

A packaged resonator includes a substrate, an acoustic stack, a first polymer layer and a second polymer layer. The acoustic stack is disposed over the substrate. The first polymer layer is disposed over the substrate surrounding the acoustic stack. The first polymer layer also provides a first air gap above the acoustic stack. The second polymer layer is disposed over the acoustic stack and above the first air gap.

Packaged resonator with polymeric air cavity package

An acoustic resonator comprises a substrate comprising a cavity. The electrical resonator comprises a resonator stack suspended over the cavity. The resonator stack comprises a first electrode; a second electrode; a piezoelectric layer; and a temperature compensating layer comprising borosilicate glass (BSG).

Electrical resonator

An acoustic resonator device including a piezoelectric layer, a first electrode disposed adjacent to a first surface of the piezoelectric layer, and a second electrode disposed adjacent to a second surface of the piezoelectric layer. At least one of the first electrode and the second electrode includes a first conductive layer disposed adjacent to the piezoelectric layer and having a first acoustic impedance, and a second conductive layer disposed on a side of the first conductive layer opposite the piezoelectric layer and having a second acoustic impedance greater than the first acoustic impedance. The acoustic resonator device further includes at least one lateral feature for increasing quality factor Q of the acoustic resonator structure. The at least one lateral feature includes at least one of an air-ring between the piezoelectric layer and the second electrode, and a frame on at least one of the first electrode and the piezoelectric layer.

Acoustic resonator comprising acoustic redistribution layers and lateral features

An acoustic resonator comprises a first electrode, a second electrode and a piezoelectric layer disposed between the first electrode and the second electrode, and comprising a C-axis having an orientation. A polarization-determining seed layer (PDSL) is disposed beneath the piezoelectric layer, the seed layer comprising a metal-nonmetal compound. A method of fabricating a piezoelectric layer over a substrate comprises forming a first layer of a polarization determining seed layer (PDSL) over the substrate. The method further comprises forming a second layer of the PDSL over the first layer. The method further comprises forming a first layer of a piezoelectric material over the second layer of the PDSL; and forming a second layer of the piezoelectric material over the first layer of the piezoelectric material. The piezoelectric material comprises a compression axis (C-axis) oriented along a first direction.

Polarity determining seed layer and method of fabricating piezoelectric materials with specific C-axis

An acoustic resonator structure comprises a first electrode disposed on a substrate, a piezoelectric layer disposed on the first electrode, a second electrode disposed on the piezoelectric layer, and an air cavity disposed in the substrate below at least a portion of a main membrane region defined by an overlap between the first electrode. The acoustic resonator structure may further comprise various integrated structures at or around the main membrane region to improve its electrical performance.

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Westminster, CO, United States of America

John Choy