A MEMS resonator is provided with improved electrical characteristics and reduced spurious resonances. The MEMS resonator includes two or more first rectangular resonator plates with lengths greater than their respective widths. Moreover, the MEMS resonator includes two or more second rectangular resonator plates that are positioned parallel to the first resonator plates in the widthwise direction of the MEMS resonator. The length of the second resonator plates is different than the length of the first resonator plates to reduce spurious resonances.

A micro-electrical-mechanical system (MEMS) guided wave device includes a piezoelectric layer including multiple thinned regions of different thicknesses each bounding in part a different recess, different groups of electrodes on or adjacent to different thinned regions and arranged for transduction of lateral acoustic waves of different wavelengths in the different thinned regions, and at least one bonded interface between the piezoelectric layer and a substrate. Optionally, a buffer layer may be intermediately bonded between the piezoelectric layer and the substrate. Methods of producing such devices include locally thinning a piezoelectric layer to define multiple recesses, bonding the piezoelectric layer on or over a substrate layer to cause the recesses to be bounded in part by either the substrate or an optional buffer layer, and defining multiple groups of electrodes on or over the different thinned regions.

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.

A micro-electrical-mechanical system (MEMS) guided wave device includes a single crystal piezoelectric layer and at least one guided wave confinement structure configured to confine a laterally excited wave in the single crystal piezoelectric layer. A bonded interface is provided between the single crystal piezoelectric layer and at least one underlying layer. A multi-frequency device includes first and second groups of electrodes arranged on or in different thickness regions of a single crystal piezoelectric layer, with at least one guided wave confinement structure. Segments of a segmented piezoelectric layer and a segmented layer of electrodes are substantially registered in a device including at least one guided wave confinement structure.

A method of making an acoustic wave sensor includes the steps of providing a piezoelectric substrate layer and printing on the substrate layer a sensor layer comprising a first interdigitated acoustic wave transducer, a sensing film, and positioned on an opposing side of the sensing film from the first interdigitated acoustic wave transducer at least one selected from the group consisting of a second interdigitated acoustic wave transducer and a Bragg reflector. An insulation layer can be printed. An antenna can be printed in an antenna layer, and the insulation layer can be interposed between the antenna layer and the sensor layer. An electrical connection can be printed between the antenna and the first interdigitated acoustic wave transducer. An acoustic wave sensor is also disclosed.

A micro-electrical-mechanical system (MEMS) guided wave device includes a single crystal piezoelectric layer and at least one guided wave confinement structure configured to confine a laterally excited wave in the single crystal piezoelectric layer. A bonded interface is provided between the single crystal piezoelectric layer and at least one underlying layer. A multi-frequency device includes first and second groups of electrodes arranged on or in different thickness regions of a single crystal piezoelectric layer, with at least one guided wave confinement structure. Segments of a segmented piezoelectric layer and a segmented layer of electrodes are substantially registered in a device including at least one guided wave confinement structure.

A micro-electrical-mechanical system (MEMS) guided wave device includes a piezoelectric layer including multiple thinned regions of different thicknesses each bounding in part a different recess, different groups of electrodes on or adjacent to different thinned regions and arranged for transduction of lateral acoustic waves of different wavelengths in the different thinned regions, and at least one bonded interface between the piezoelectric layer and a substrate. Optionally, a buffer layer may be intermediately bonded between the piezoelectric layer and the substrate. Methods of producing such devices include locally thinning a piezoelectric layer to define multiple recesses, bonding the piezoelectric layer on or over a substrate layer to cause the recesses to be bounded in part by either the substrate or an optional buffer layer, and defining multiple groups of electrodes on or over the different thinned regions.

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.

An acoustic resonator includes a piezoelectric stack including a piezoelectric layer having a top surface and a bottom surface, a top electrode layer disposed above the top surface, and a bottom electrode layer disposed below the bottom surface. A number of acoustic wave reflectors are disposed on a side of the bottom electrode layer opposite the piezoelectric layer. Each acoustic wave reflector includes a high acoustic impedance layer and may include a low acoustic impedance layer. The acoustic resonator may include a tether that extends laterally to a stacking direction of the layers of the piezoelectric stack. A supporting structure may be coupled to the tether opposite the acoustic resonator for anchoring the acoustic resonator. A mirror, one or more phononic crystals, or both may be positioned on proximate the tether opposite the acoustic resonator to avoid resonant waves from exiting the acoustic resonator in use.

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.