A mechanical resonator includes two identical plates, and a decoupling structure comprising at least two first connectors, each first connector connecting the decoupling structure to a respective one of the two identical plates, and an anchor disposed at a center of the decoupling structure. Each of the two identical plates may be a square plate adapted to resonate in Lam?-mode. Further, each of the two identical plates may comprise a plurality of square plates, each square plate disposed next to one another. The decoupling structure further comprises a first ring connected to each of the two identical plates via a respective one of the at least two first connectors. The decoupling structure may further comprise a second ring connected to an inside of the first ring via at least two second connectors, wherein the anchor is disposed at a center of the second ring.

A MEMS resonator is provided with a high quality factor and lower motional impedance. The MEMS resonator includes a silicon layer having opposing surfaces, a piezoelectric layer above one of the surfaces of the silicon layer, and a pair of electrodes disposed on opposing surfaces of the piezoelectric layer, respectively. Moreover, the piezoelectric layer has a crystallographic axis that extends at an angle relative to the vertical axis of the MEMS resonator.

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.

Reference oscillators are ubiquitous in timing applications generally, and in modern wireless communication devices particularly. Microelectromechanical system (MEMS) resonators are of particular interest due to their small size and potential for integration with other MEMS devices and electrical circuits on the same chip. In order to support their use in high volume low cost applications it would be beneficial for MEMS designers to have MEMS resonator designs and manufacturing processes that whilst employing low cost low resolution semiconductor processing yield improved resonator performance thereby reducing the requirements of the oscillator circuitry. It would be further beneficial for the oscillator circuitry to be able to leverage the improved noise performance of differential TIAs without sacrificing power consumption.

A vibration device that includes a vibration portion, a support portion connected to the vibration portion, a bending-vibrating portion connected to the support portion, and a frame-shaped base portion connected to the bending-vibration portion and disposed so as to surround the vibration portion. The base portion defines a slit that extends in a first direction crossing a second direction in which the support portion extends from the vibration portion, the slit defining first and second fixed ends of the bending-vibrating portion and which are continuous with the base portion. A length between a portion of the bending-vibrating portion connected to the support portion to one of the first and second fixed ends of the bending-vibrating portion is in a range of /8 to 3/8, where denotes a wavelength of a bending vibration corresponding to a frequency of a characteristic vibration of the vibration portion.

A resonator that includes a vibrating portion that has a piezoelectric film, and a lower and upper electrodes that face each other with the piezoelectric film interposed therebetween. Moreover, a holding portion is provided at least around a maximum displacement region of the vibrating portion and has an insulating film. A holding arm connects the vibrating portion and the holding portion, and include a conductive portion that is in contact with the insulating film of the holding portion in at least a region that faces the maximum displacement region of the vibrating portion. In addition, the conductive portion is electrically connected to the lower electrode or the upper electrode or is grounded.

An example resonating structure comprises a substrate, a resonator body, and an anchoring body for anchoring the resonator body to the substrate. The resonator body is doped with a dopant having a concentration chosen so as to minimize a second order temperature coefficient of frequency for the resonator body. The resonator body is operable in an in-plane mode of vibration and an out-of-plane mode of vibration.

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/T4 and y=0.85(1/T)+0.570.05 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.

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 MEMS device may include: (i) a lower cavity, including a first island, formed within a first layer of the MEMS device; (ii) an upper cavity, including a second island, formed within a second layer of the MEMS device; (iii) a MEMS resonating element arranged in a device layer of the MEMS device and anchored via the first and second islands; (iv) a first set of electrodes for electrostatic actuation and sensing of the MEMS resonating element in an in-plane mode that is arranged in the device layer of the MEMS device; and (v) a second set of electrodes for electrostatic actuation and sensing of the MEMS resonating element in an out-of-plane mode that is electrically isolated from the first set of electrodes and located in the first or second layer of the MEMS device, and wherein the out-of-plane mode is a torsional mode or a saddle mode.