A resonator is provided that includes a vibration portion having a first and second electrodes, a piezoelectric film disposed therebetween and having a first face opposing the first electrode, and at least two temperature characteristic adjustment films formed to oppose the first face of the piezoelectric film with the first electrode interposed therebetween. Moreover, the resonator includes a frame that surrounds at least part of the vibration portion; and a holding arm connecting the vibration portion to the holding portion. The vibration portion includes a surface opposing the first face of the piezoelectric film and having first and second regions in which an average amount of displacement is larger than an average amount of displacement in the first region when the vibration portion vibrates.

A resonator that includes a substrate, an insulating film that is formed on the substrate, and vibration regions each of which is formed on the insulating film and includes lower electrodes that are formed on the insulating film, a piezoelectric film that is formed on the lower electrodes, and an upper electrode that is formed on the piezoelectric film. At least one lower electrode of the lower electrodes that are formed on the insulating film has an electric potential that differs from an electric potential of another lower electrode such that at least one vibration region vibrates in antiphase with another vibration region. Moreover, a package seals a resonator and includes the substrate, the insulating film, and the vibration regions and includes a ground terminal for grounding the substrate.

MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.

A vibrator that includes a silicon substrate, an electrode facing a surface of the silicon substrate, and a piezoelectric body between the silicon substrate and the electrode and that produces contour vibration in a plane along the surface of the silicon substrate in accordance with a voltage applied to the electrode. The vibrator includes one or more substantially rectangular vibration regions each having a long side parallel to a node of the contour vibration of the piezoelectric body and a short side orthogonal to the node of the contour vibration of the piezoelectric body and corresponding to a half-wavelength of the contour vibration. The resonator satisfies W/T≥4 and y=−0.85×(1/T)+0.57±0.05 where T is the thickness of the silicon substrate, W is the width of the short side of the vibration region, and y is the resistivity of the silicon substrate.

A micromechanical vibrasolator isolates vibration of a micromechanical resonator and includes: phononic bandgap mirrors, monophones connected serially; phonophore arms in an alternating sequence of phonophore arm-monophone-phonophore arm; abutments in acoustic communication with the phononic bandgap mirrors; wherein the micromechanical resonator is interposed between the phononic bandgap mirrors with phononic bandgap mirror arranged in parallel on opposing sides of the micromechanical resonator arranged perpendicular to a direction of vibration of an in-plane vibrational mode of the micromechanical resonator.

A microelectromechanical system (MEMS) resonator includes a degenerately-doped single-crystal silicon layer and a piezoelectric material layer disposed on the degenerately-doped single-crystal silicon layer. An electrically-conductive material layer is disposed on the piezoelectric material layer opposite the degenerately-doped single-crystal silicon layer, and patterned to form first and second electrodes.

A resonator with stabilized resonant frequency that includes a lower electrode, a plurality of upper electrodes, and a piezoelectric film disposed between the lower electrode and the plurality of upper electrodes. Moreover, an upper lid having a first and second opposing surfaces is provided so that the first surface faces and seals a first surface of the resonator. In addition, a lower lid having a first and second opposing surfaces is provided so that the first surface faces and seals a second surface of the resonator. The resonator further includes a power terminal electrically connected to the upper electrodes and a ground terminal provided on the second surface of the upper lid. The lower electrode is electrically connected to the ground terminal by the upper lid.

A suspended device structure comprises a substrate, a cavity disposed in a surface of the substrate, and a device suspended entirely over a bottom of the cavity. The device is a piezoelectric device and is suspended at least by a tether that physically connects the device to the substrate. The tether has a non-linear centerline. A wafer can comprise a plurality of suspended device structures.

A suspended device structure comprises a substrate, a cavity disposed in a surface of the substrate, and a device suspended entirely over a bottom of the cavity. The device is a piezoelectric device and is suspended at least by a tether that physically connects the device to the substrate. The tether has a non-linear centerline. A wafer can comprise a plurality of suspended device structures. A device structure can comprise a device over a sacrificial portion or cavity and a tether with a tether opening extending to the sacrificial portion or cavity. The tether or tether opening can have a T shape. The tether can have a tether length at least one third as large as a device length and the device can have a device length at least twice as large as a device width.

A MEMS (microelectromechanical system) resonator with a material layer of single-crystalline silicon, at least one layer made of material with low thermal diffusivity to reduce thermoelastic dissipations in the MEMS resonator, a layer of piezoelectric material, and a layer made of electrically conducting material. The said-layer with low thermal diffusivity is between the single-crystalline silicon layer and the piezoelectric layer, or between the piezoelectric layer and the electrically conducting layer. The use of a material layer of low thermal diffusivity.