Guided wave devices with embedded electrodes and non-embedded electrodes
AssigneeQorvo US, Inc.
InventorKushal Bhattacharjee
Life of this patent
Estimating the term…
Abstract
A micro-electrical-mechanical system (MEMS) guided wave device includes a plurality of electrodes arranged below a piezoelectric layer (e.g., either embedded in a slow wave propagation layer or supported by a suspended portion of the piezoelectric layer) and configured for transduction of a lateral acoustic wave in the piezoelectric layer. The piezoelectric layer permits one or more additions or modifications to be made thereto, such as trimming (thinning) of selective areas, addition of loading materials, sandwiching of piezoelectric layer regions between electrodes to yield capacitive elements or non-linear elastic convolvers, addition of sensing materials, and addition of functional layers providing mixed domain signal processing utility.
Claims20
A micro-electrical-mechanical system (MEMS) guided wave device comprising:
- a single crystal piezoelectric layer;
- a slow wave propagation layer disposed below the single crystal piezoelectric layer;
- at least one embedded electrode arranged in the slow wave propagation layer;
- at least one top side electrode arranged over the single crystal piezoelectric layer;
- and
- a guided wave confinement structure arranged proximate to the slow wave propagation layer;
- wherein either (i) the at least one embedded electrode or (ii) the at least one top side electrode comprises a plurality of electrodes configured for transduction of at least one lateral acoustic wave in the single crystal piezoelectric layer;
- wherein the guided wave confinement structure is configured to confine the at least one lateral acoustic wave in the single crystal piezoelectric layer and the slow wave propagation layer;
- wherein at least one region of the single crystal piezoelectric layer is sandwiched between an embedded electrode of the at least one embedded electrode and a top side electrode of the at least one top side electrode;
- and
- wherein at least one of (a) a portion of the single crystal piezoelectric layer or (b) any one or more of the at least one top side electrode, is exposed along a top side of the MEMS guided wave device.
A method of fabricating a MEMS guided wave device, the method comprising:
- providing at least one embedded electrode in a slow wave propagation layer;
- arranging a single crystal piezoelectric layer over the slow wave propagation layer;
- providing at least one top side electrode over the single crystal piezoelectric layer;
- and
- providing a guided wave confinement structure proximate to the slow wave propagation layer;
- wherein either (i) the at least one embedded electrode or (ii) the at least one top side electrode comprises a plurality of electrodes configured for transduction of a lateral acoustic wave in the single crystal piezoelectric layer;
- wherein the guided wave confinement structure is configured to confine the lateral acoustic wave in the single crystal piezoelectric layer and the slow wave propagation layer;
- wherein one or more regions of the single crystal piezoelectric layer are sandwiched between (i) one or more embedded electrodes of the at least one embedded electrode and (ii) one or more top side electrodes of the at least one top side electrode;
- and
- wherein at least one of (a) a portion of the single crystal piezoelectric layer or (b) any one or more of the at least one top side electrode, is exposed along a top side of the MEMS guided wave device.
A micro-electrical-mechanical system (MEMS) guided wave device comprising:
- a single crystal piezoelectric layer;
- a substrate;
- a cavity or recess arranged between the substrate and a suspended portion of the single crystal piezoelectric layer;
- a first group of input electrodes configured for transduction of a first lateral acoustic wave in the suspended portion of the single crystal piezoelectric layer;
- a second group of input electrodes configured for transduction of a second lateral acoustic wave in the suspended portion of the single crystal piezoelectric layer;
- and
- an output electrode comprising a first plate arranged over the suspended portion of the single crystal piezoelectric layer and a second plate arranged under the suspended portion of the single crystal piezoelectric layer;
- wherein the first group of input electrodes, the second group of input electrodes, and the output electrode are configured to interact with the single crystal piezoelectric layer to provide non-linear elastic convolver utility.
Dependencies are inferred from the claim text.