A temperature sensor is a temperature sensor using a MEMS resonator, and includes: a MEMS resonator; a sweeper that sweeps a frequency of an excitation signal for a vibrator of the MEMS resonator in a predetermined sweep direction, and outputs the excitation signal swept to the MEMS resonator; a discontinuity point detector that obtains a vibration state information signal, which is a characteristic quantity expressing a vibration state of the vibrator based on the excitation signal, from the MEMS resonator, and detects a detection value that is (i) a frequency of the excitation signal when the vibration state information signal obtained changes discontinuously or (ii) a time corresponding to the frequency; and a converter that determines a physical quantity acting on the MEMS resonator based on the detection value detected.

An MEMS device includes: a first member; a second member forming a sealed space with the first member therebetween; and a third member disposed between the first member and the second member and joined to the first member and the second member, in which the third member has lower rigidity than rigidity of the first member and the second member, and the third member is provided with a communication portion that establishes communication between the sealed space and an external space.

Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

A system and/or method for utilizing MEMS switching technology to operate MEMS sensors. As a non-limiting example, a MEMS switch may be utilized to control DC and/or AC bias applied to MEMS sensor structures. Also for example, one or more MEMS switches may be utilized to provide drive signals to MEMS sensors (e.g., to provide a drive signal to a MEMS gyroscope).

A sensor chip includes a first substrate with a first surface and a second surface including at least one CMOS circuit, a first MEMS substrate with a first surface and a second surface on opposing sides of the first MEMS substrate, a second substrate, a second MEMS substrate, and a third substrate including at least one CMOS circuit. The first surface of the first substrate is attached to a packaging substrate and the second surface of the first substrate is attached to the first surface of the first MEMS substrate. The second surface of the first MEMS substrate is attached to the second substrate. The first substrate, the first MEMS substrate, the second substrate and the packaging substrate are provided with electrical inter-connects.

A low-profile packaging structure for a microelectromechanical-system (MEMS) resonator system includes an electrical lead having internal and external electrical contact surfaces at respective first and second heights within a cross-sectional profile of the packaging structure and a die-mounting surface at an intermediate height between the first and second heights. A resonator-control chip is mounted to the die-mounting surface of the electrical lead such that at least a portion of the resonator-control chip is disposed between the first and second heights and wire-bonded to the internal electrical contact surface of the electrical lead. A MEMS resonator chip is mounted to the resonator-control chip in a stacked die configuration and the MEMS resonator chip, resonator-control chip and internal electrical contact and die-mounting surfaces of the electrical lead are enclosed within a package enclosure that exposes the external electrical contact surface of the electrical lead at an external surface of the packaging structure.

An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

A dual-shell architecture and methods of fabrication of fused quartz resonators is disclosed. The architecture may include two encapsulated and concentric cavities using plasma-activated wafer bonding followed by the high-temperature glassblowing. The dual-shell architecture can provide a protective shield as well as a “fixed-fixed” anchor for the sensing element of the resonators. Structures can be instrumented to operate as a resonator, a gyroscope, or other vibratory sensor and for precision operation in a harsh environment. Methods for fabricating a dual-shell resonator structure can include pre-etching cavities on a cap wafer, pre-etching cavities on a device wafer, bonding the device wafer to a substrate wafer to form a substrate pair and aligning and bonding the cap wafer to the substrate pair to form a wafer stack with aligned cavities including a cap cavity and a device cavity. The wafer stack may be glassblown to form a dual-shell structure.

Three-dimensional (3D) micro-scale shells are presented with openings of various sizes and geometries on the surface. The shell consist of a suspended ring-shaped resonator, multiple support beams, a support post, and a cap region that connects the support beams to the support post. Shells with openings of various sizes and geometries allow the creation of micro electromechanical systems (MEMS) sensors and actuators with a wide range of engineered mechanical and electrical properties. The openings on the shell surface can, for example, control the mechanical quality factor (Q) and resonance frequencies of the shell when the shell is used as a suspended proof mass of a mechanical resonator of a vibratory gyroscope. The shells can also serve as mechanical supporting layers and/or an electrode connection layer for MEMS actuators and sensors that use 3D shells as proof masses.

An online trimming device and method for a micro-shell resonator gyroscope is provided. A micro-shell resonator gyroscope fixing fixture and a mode test circuit in the device are placed in a vacuum test cavity provided with a circuit interface. The mode test circuit and a host computer are connected through a circuit interface on the vacuum test cavity. The gyroscope fixing fixture is provided with a signal interface, and the electrodes on the gyroscope substrate are connected to the signal interface. The signal interface on the fixture is connected to the mode test circuit. The laser etching module is located at the top of the device. An opening is formed in the gyroscope fixing fixture. The vacuum test cavity is provided with a transparent trimming window. The laser acts on the edge of the resonant structure of the gyroscope through the trimming window and the through hole of the fixture.