Guided wave devices with embedded electrodes and non-embedded electrodes

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;
• and
• 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.

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.