Provided are micromechanical resonators and resonator systems including the micromechanical resonators. The micromechanical resonators may each include a supporting beam including a fixed end fixed on a supporting member and a loose end configured to vibrate, and a lumped mass arranged on the loose end, wherein the loose end has a width greater than a width of the fixed end, and a width of the lumped mass is greater than that the width of the fixed end.

A dual-mode resonator, devices employing the dual-mode resonator, and the methods of making the resonator and the devices are disclosed. Embodiments include a dual-mode resonator including a semiconductor substrate; a material on the semiconductor substrate, having a cavity formed therein; a seed layer over the cavity in a V-shape, wherein sides of the V-shape form an angle of 15 to 25 degrees with a horizontal line; a bottom electrode on the seed layer; an acoustic layer on the bottom electrode; a top electrode on the acoustic layer; and a mass loading layer on the top electrode; and a cap over the dual-mode resonator.

A method of an open loop characterization of an electrostatic MEMS based resonator with a varying gap, the method including: converting, via a trans-impedance amplifier circuit, an output current signal of the resonator into a voltage; multiplying the output current signal converted into the voltage, by means of a multiplier circuit, with an AC signal or with a different signal at a frequency of the resonator and carrying a second harmonic signal to a main tone; and measuring a frequency response of a signal cleared of frequencies apart from the main tone using a network analyzer.

A resonator is provided that includes a vibration part and a mass addition portion. The vibration part includes a piezoelectric film, an upper electrode, and a lower electrode. The upper electrode and the lower electrode are disposed on opposite sides with the piezoelectric film therebetween. The amount of displacement of the vibration part is greater in a region corresponding to at least part of the mass addition portion than in any other region. The mass addition portion has an inclined surface that slopes in such a manner that the mass addition portion has end regions and a central region thinner than at least one of the end regions when the vibration part is viewed in a plan view.

A resonator includes a base, at least one vibration arm, a frame, and a holding arm. The vibration arm includes a piezoelectric film, an upper electrode, and a lower electrode. The inequality Fs/Fm<1.9 or the inequality 2.1<Fs/Fm holds, where Fm is a frequency of a main or primary mode in the vibration arm, and Fs is a frequency of a spurious mode in the holding arm.

The invention relates to a mechanical oscillator device comprising an unsupported membrane with a multitude of discrete mass elements distributed to form Phononic crystal cells in the form of regions of additional mass each comprising a plurality of mass elements. The phononic crystal structure has a defect for confining a mechanical oscillation mode having a resonance frequency, f, with the mass elements have a smallest lateral dimension of less than 1/10 of a wavelength of the mechanical oscillation mode. The invention is based on a distribution of tiny additional mass elements providing a periodic density contrast pattern to create the bandgap. This approach keeps the tensile stress uniform which ensures perfect overlap between the tensile stress distribution and mode-shape. This again reduces the damping and thus allows for very high quality factors, Q.

According to various embodiments, there is provided a micro-electromechanical resonator, including a substrate with a cavity therein; and a resonating structure suspended over the cavity, the resonating structure having a first end anchored to the substrate, wherein the resonating structure is configured to flex in a flexural mode along a width direction of the resonating structure, wherein the width direction is defined at least substantially perpendicular to a length direction of the resonating structure, wherein the length direction is defined from the first end to a second end of the resonating structure, wherein the second end opposes the first end.

Provided are micromechanical resonators and resonator systems including the micromechanical resonators. The micromechanical resonators may each include a supporting beam including a fixed end fixed on a supporting member and a loose end configured to vibrate, and a lumped mass arranged on the loose end, wherein the loose end has a width greater than a width of the fixed end, and a width of the lumped mass is greater than that the width of the fixed end.

A gallium nitride structure that includes: a substrate; a gallium nitride layer opposed to the substrate and containing gallium nitride as a main component thereof; and a first electrode between the gallium nitride layer and the substrate. The first electrode includes at least one hafnium layer containing a single metal of hafnium as a main component thereof, and the at least one hafnium layer is in contact with the gallium nitride layer.

A logic system includes a microelectromechanical system, MEMS, resonator having an arch beam and first and second side beams, wherein the first side beam is attached with a first end to a first end of the arch beam and the second side beam is attached with a first end to a second end of the arch beam to form a U-shape; an input electrode facing the second side beam; a selector electrode facing the second side beam; a first output electrode facing the first side beam; and a second output electrode facing the arch beam.