A method of manufacturing a piezoelectric resonator unit that includes mounting a piezoelectric resonator on a base member using a conductive adhesive, keeping the piezoelectric resonator in an environment having a temperature and a humidity higher than those of a surrounding region for a predetermined time, performing frequency adjustment of the piezoelectric resonator by etching using an ion beam, and joining a lid member to the base member using a joining material such that the piezoelectric resonator is hermetically sealed between the lid member and the base member.

A tunable non-reciprocal frequency limiter with an asymmetric micro-electro-mechanical resonator has two independent transducer ports. One port has a film stack including a 10 nm hafnium zirconium oxide (HZO) and another port has a film stack including a 120 nm aluminum nitride (AlN) film. These film stacks are deposited on top of 70 nm single crystal silicon substrate applying CMOS compatible fabrication techniques. The asymmetric transducer architecture with dissimilar electromechanical coupling coefficients force the resonator into mechanical nonlinearity on actuation with transducer having larger coupling. A proof-of-concept electrically-coupled channel filter is demonstrated with two such asymmetric resonators at 253 MHz with individual Q.sub.res of 870 and a non-reciprocal transmission ratio (NTR) 16 dB and BW.sub.3dB of 0.25%.

An apparatus includes a microelectromechanical system (MEMS) die having a first surface and an opposing second surface. The MEMS die includes a surface-mounted resonator on the first surface and includes a first inductor. The apparatus also includes first and second dies. The first die has a third surface and an opposing fourth surface. The first die is coupled to the MEMS die such that the third surface of the first die faces the first surface of the MEMS die. The first and second surfaces are spaced apart. The first die includes an oscillator circuit and a second inductor. The oscillator circuit is coupled to the second inductor. The second inductor is inductively coupled to the first inductor. The second die is electrically coupled to the first die.

In one embodiment, a resonator gyroscope device comprises: a sealed vacuum cavity; a resonator positioned within the cavity, wherein the resonator comprises a resonating shell coupled to a stem; at least one light source that generates an optical excitation signal directed onto the resonating shell of the resonator; a controller coupled to the light source; at least one optical signal interrogation device; and measurement processor coupled to the at least one optical signal interrogation device; wherein the controller controls the at least one light source to selectively heat a portion of the resonating shell in a manner that excites the resonating shell into a state of resonance; wherein the at least one optical signal interrogation device measures a movement of a standing wave in the resonating shell and the measurement processor outputs rotational data based on the movement measured by the at least one optical signal interrogation device.

A microelectromechanical resonant circulator device is providing, having a substrate, and at least three electrical ports supported on the substrate. At least three electromechanical resonator elements are connected with associated switch elements and an associated port. The switch elements are operative to provide commutation over time of the electromechanical resonator elements.

A piezoelectric device includes a piezoelectric body at least a portion of which can bend and vibrate, an upper electrode on an upper surface of the piezoelectric body and in which distortion of a crystal lattice is reduced as a distance from the upper surface of the piezoelectric body increases, a lower electrode on a lower surface of the piezoelectric body and in which distortion of a crystal lattice is reduced as a distance from the upper surface of the piezoelectric body increases, and a support substrate below the piezoelectric body, in which a recess extending from a lower surface of the support substrate toward the lower surface of the piezoelectric device is provided.

A piezoelectric device includes a piezoelectric single crystal body with a homogeneous polarization state and of which at least a portion flexurally vibrates, an upper electrode on an upper surface of the piezoelectric single crystal body, a lower electrode on a lower surface of the piezoelectric single crystal body, and a supporting substrate below the piezoelectric single crystal body. A recess extends from a lower surface of the supporting substrate toward the lower surface of the piezoelectric single crystal body.

Three-dimensional (3D) micro-scale shells are presented with selectively removed regions/openings and which can be used in sensors and actuators, including gyroscopes. Example shells consisting of a suspended ring-shaped resonator that is supported using multiple beams that are not in the plane of the ring and are attached to a support post can be formed. Shells with various sizes and geometries of selectively removed regions and openings allow the creation of micro electromechanical systems (MEMS) sensors and actuators with a wide range of engineered mechanical and electrical properties. These shells can be used to form stacked 3D structures for various types of MEMS sensor and actuator devices, such as resonant gyroscopes, with sense and drive electrodes that conform to the curved profile of the resonant shell using for gyroscopes. 3D shells formed from a starting parent substrate are released and separated from their parent substrate using a number of techniques.

A vibrator is provided that includes a substrate having a major surface defined in width and length directions and one or more electrodes formed at least in a substantial entire region of the major surface of the substrate in the length direction, and that performs, as main vibration, expansion-contraction vibration along the width direction in accordance with a voltage applied to the electrodes. Moreover, a holder surrounds at least a portion of the vibrator; and a holding arm connects the vibrator to the holder. Moreover, the vibrator has a width Wo in the width direction positioned at an end in the length direction and includes, to have a width Wm differing from the width Wo and positioned between a pair of ends opposing in the length direction, a variant portion at least one or more locations that is in a shape recessed or projecting in the width direction.

Examples of the present invention include unreleased coupled multi-cavity resonators and transmission filters. In some examples, the resonators include resonant cavities coupled by acoustic couplers (ABGCs) and acoustic reflectors (ABRs). These acoustic components enable improved confinement of acoustic modes within the resonator to increase the quality factor (Q) and lower the motional resistance (R.sub.x). A coupled resonator with 5 cavities coupled by 4 ABGCs can achieve a Q of 1095 while a single-cavity resonator of the same device size has a Q of 760. In some examples, the devices can be configured to work as electronic transmission filters in at least two types of filter configurations. In the transmission line filter configuration, the device can include a filter structure in an arrangement (LH).sup.N H (LH).sup.N, defined as a Fabry-Perot Resonator (FPR). In the multi-pole filter configuration, the device can include a filter structure in an arrangement similar to the multi-cavity resonator design.