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 includes a layer of base material and, deposited on top of the layer of base material, a layer of mismatch material having a mismatch in temperature coefficient of elasticity (TCE) relative to the base material. The base material 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 thickness of the layer of the mismatch material is chosen so as to minimize a first order temperature coefficient of frequency for the resonator body.

The present disclosure provides a resonator which resonates in a bulk acoustic wave mode. The resonator includes a resonator body, at least one transducer arm and a substrate. The resonator body is deformed at least along a first direction. The transducer arm is connected to the resonator body along the first direction and includes a base, a piezoelectric layer and an electrode layer. The base includes a first end connected to the resonator body. The piezoelectric layer is disposed above the base but not extended to the resonator body, and the electrode layer is disposed above the piezoelectric layer but not extended to the resonator body. The substrate is for securing the transducer arm such that the resonator body is suspended.

A resonance device with improved precision of temperature control. The resonance device includes a platform; a resonator including a vibrator and one or more holding arms that connect the vibrator and the platform to each other such that a first groove is provided around the vibrator. Moreover, the resonance device includes a sensor with a measurement portion that measures temperature and a heater formed on the platform. A second groove is provided between the measurement portion and the heater.

A MEMS resonator array is provided with improved electrical characteristics and reduced motional impedance at high frequency applications. The MEMS resonator array includes a pair of first piezoelectric resonators that are opposed to each other with a space defined therebetween. Moreover, the MEMS resonator array includes a pair of second piezoelectric resonators that are opposed to each other and that are each coupled to respective corners of each of the first piezoelectric resonators. As such, each of the second piezoelectric resonators is partially disposed in the space defined between the pair of first piezoelectric resonators.

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.

The present disclosure provides an aerosol sensing method. The aerosol sensing method includes steps of providing an entering process, providing a particle collecting process and providing a measuring process. The entering process is to allow an aerosol to enter a chamber of a thermal-piezoresistive oscillator-based aerosol sensor, and a thermal-piezoresistive resonator is disposed in the chamber. The particle collecting process is to allow particulate matters in the aerosol to land on at least one proof-mass of the thermal-piezoresistive resonator when the thermal-piezoresistive resonator is not driven. The measuring process is to use an electrical signal to drive the thermal-piezoresistive resonator and measure a resonant frequency of the thermal-piezoresistive resonator. The particle collecting process and the measuring process are operated in a repetitive cycle for measuring changes of the resonant frequency of the thermal-piezoresistive resonator to measure the particulate matters of the aerosol.

The present disclosure provides a resonator which resonates in a bulk acoustic wave mode. The resonator includes a resonator body, at least one transducer arm and a substrate. The resonator body is deformed at least along a first direction. The transducer arm is connected to the resonator body along the first direction and includes a base, a piezoelectric layer and an electrode layer. The base includes a first end connected to the resonator body. The piezoelectric layer is disposed above the base but not extended to the resonator body, and the electrode layer is disposed above the piezoelectric layer but not extended to the resonator body. The substrate is for securing the transducer arm such that the resonator body is suspended.

In a quartz crystal unit, the unit comprising a quartz crystal resonator having a base portion, and first and second tuning fork arms connected to the base portion, the base portion having a length less than 0.5 mm and greater than a spaced-apart distance between the first and second tuning fork arms, each of the first and second tuning fork arms having a width less than 0.1 mm and a length less than 1.56 mm, and a plurality of different widths including a first width and a second width greater than the first width, at least one groove being formed in at least one of opposite main surfaces of each of the first and second tuning fork arms so that a length of the at least one groove is within a range of 0.3 mm to 0.79 mm, the quartz crystal resonator being housed in a case, and a lid being connected to the case.

Particle detection device comprising a support, a platform for receiving particles, four beams suspending the platform from the support, such that the platform can be made to vibrate, means for making said platform vibrate at a resonance frequency, means for detecting the displacement of the platform in a direction of displacement. Each beam has a length I, a width L and a thickness e and the platform has a dimension in the direction of displacement of the platform and in which in a device with out of plane mode I?10?L and the dimension of each beam in the direction of displacement of the platform is at least 10 times smaller than the dimension of the platform in the direction of displacement.

The present disclosure describes a micromechanical resonator comprising a resonator element (40) having a length (l.sub.1) and a width (w.sub.1) that is perpendicular to the length. The resonator element has a length-to-width aspect ratio in a range of 1.8 to 2.2. The resonator element is suspended to a support structure with two or more anchors (41, 43). Each of the two or more anchors is attached to a first location or a second location. The first location is at a shorter side (42) of the resonator element. The first location divides the width (w.sub.1) of the resonator element into a larger portion (w.sub.3) and a smaller portion (w.sub.2) such that a ratio between said smaller portion (w.sub.2) and the whole width (w.sub.1) is in a range of 0.10 to 0.28. The second location is at a longer side (44). The second location divides the length (l.sub.1) of the resonator element into a larger portion (l.sub.3) and a smaller portion (l.sub.2) such that a ratio between said smaller portion (l.sub.2) and the whole length (l.sub.1) is in a range of 0.36 to 0.48.