A microelectromechanical device having a mobile structure including mobile arms formed from a composite material and having a fixed structure including fixed arms capacitively coupled to the mobile arms. The composite material includes core regions of insulating material and a silicon coating.

A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.

A resonance device is provided for reducing the influence on the resonant frequency of the resonance device of the electric charge borne by an insulating film of a frame. The resonance device includes a resonator including a vibration portion and a frame disposed in at least a part of a vicinity of the vibration portion. The frame includes a holding body and an insulating film, with the holding body holding the vibration portion to vibrate and the insulating film being formed above the holding body. A lower cover is provided having a recess forming at least a part of a space in which the vibration portion vibrates. An inner side surface of the insulating film is disposed at a first distance from an inner surface of a side wall defining the recess.

A MEMS (microelectromechanical system) resonator with a material layer of single-crystalline silicon, at least one layer made of material with low thermal diffusivity to reduce thermoelastic dissipations in the MEMS resonator, a layer of piezoelectric material, and a layer made of electrically conducting material. The said-layer with low thermal diffusivity is between the single-crystalline silicon layer and the piezoelectric layer, or between the piezoelectric layer and the electrically conducting layer. The use of a material layer of low thermal diffusivity.

The present disclosure relates to a MEMS vibrator or the like that has excellent chemical resistance and an excellent mechanical strength and that is easily thinned. The present disclosure is a MEMS vibrator comprising: a vibrating film including a graphite film; and a silicon member supporting the vibrating film, the graphite film having a thickness of 50 nm or more and less than 20 m, and the graphite film having a Young's modulus along a graphite film plane direction of 700 GPa or more.

This invention provides electromechanical resonators based on metal chalcogenide nanotubes. The invention further provides methods of fabrication of electromechanical resonators and methods of use of such electromechanical resonators.

A microelectromechanical device having a mobile structure including mobile arms formed from a composite material and having a fixed structure including fixed arms capacitively coupled to the mobile arms. The composite material includes core regions of insulating material and a silicon coating.

A microelectromechanical device having a mobile structure including mobile arms formed from a composite material and having a fixed structure including fixed arms capacitively coupled to the mobile arms. The composite material includes core regions of insulating material and a silicon coating.

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.

A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.