Abstract: A capacitive ultrasonic transducer device includes a substrate, a first capacitive structure, a second capacitive structure, a first film structure and a second film structure. The first capacitive structure is disposed on the substrate, and includes a first electrode and a second electrode. A first gap and a dielectric layer are located between the first electrode and the second electrode. The second capacitive structure is disposed on the substrate, and includes a third electrode and a fourth electrode. A second gap is located between the third electrode and the fourth electrode. The first film structure is configured to seal the first gap. The second film structure is connected to the third electrode and the fourth electrode, and configured to seal the second gap. A first width between the first electrode and the second electrode is different from a second width of the second gap.

Abstract: A method for generating high order harmonic frequencies includes: providing a piezoelectric resonant film; and inputting a driving signal with a single tone frequency for driving the piezoelectric resonant film to oscillate in a non-linear region so as to generate a plurality of high order harmonic frequencies. Therefore, the quantity of the high order harmonic frequencies can be adjusted by applying an electrical controlling method.

Abstract: An acceleration sensing structure includes a frame, a proof mass, a gimbal and at least two outer flexible arms. The proof mass is suspended from the frame and has a first thickness. The proof mass is surrounded by and connected to the gimbal. The gimbal has a second thickness. The at least two outer flexible arms are connected between the gimbal and the frame, and the at least two outer flexible arms are arranged symmetrically. The second thickness is larger than or equal to one-half of the first thickness and is smaller than or equal to the first thickness, and when the proof mass moves, the at least two outer flexible arms are deformed.

Abstract: An acceleration sensing structure includes a frame, a proof mass, a gimbal and at least two outer flexible arms. The proof mass is suspended from the frame and has a first thickness. The proof mass is surrounded by and connected to the gimbal. The gimbal has a second thickness. The at least two outer flexible arms are connected between the gimbal and the frame, and the at least two outer flexible arms are arranged symmetrically. The second thickness is larger than or equal to one-half of the first thickness and is smaller than or equal to the first thickness, and when the proof mass moves, the at least two outer flexible arms are deformed.

Abstract: A method for generating high order harmonic frequencies includes: providing a piezoelectric resonant film; and inputting a driving signal with a single tone frequency for driving the piezoelectric resonant film to oscillate in a non-linear region so as to generate a plurality of high order harmonic frequencies. Therefore, the quantity of the high order harmonic frequencies can be adjusted by applying an electrical controlling method.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An active type temperature compensation resonator structure is provided, including a resonant body and a temperature compensation element embedded in the resonant body for a compensation current to pass therethrough. The temperature compensation element has a specified temperature coefficient of resistance that reflects the temperature of the resonant body. The magnitude of the compensated current corresponds to the reflected temperature of the resonant body. With the active type temperature compensation resonator structure, the temperature of the resonant body can be accurately reacted by the specified temperature coefficient of resistance, such that the temperature compensation element, through which the compensated current passes, can dynamically correspond to the temperature of the resonant body and accurately provide the resonant body with temperature compensation.

Abstract: A CMOS-MEMS resonant transducer and a method for fabricating the same are disclosed, which provide the CMOS-MEMS resonant transducer having narrow gaps(<500 nm) with high yield by etching a well-defined free-free beam structure, furthermore, the TiN layers disposed at the bottom of the resonant body may efficiently reduce the frequency drift due to electrostatic charges. The method for fabricating the CMOS-MEMS resonant transducer is also adapted to the processes of CMOS-MEMS platform with various scales, which provides routing and MEMS design flexibility.

Abstract: A MEMS resonator active temperature compensation method is provided. The MEMS resonator active temperature compensation method includes: a MEMS resonator is provided, wherein a structural resistance of the MEMS resonator is varied with an environmental temperature; a structural resistance shift value is formed by a variation of the environmental temperature; an electrical circuit is provided, wherein the electrical circuit is electrically connected with the MEMS resonator for providing an adjustment mechanism to the MEMS resonator; and a compensation value is provided from the adjustment mechanism for controlling the structural resistance shift value.

Abstract: An ultra low power thermally-actuated oscillator and driving circuit thereof are provided. The ultra low power thermally-actuated oscillator includes proof masses, thermally-actuated element and a plurality of driving elements. The proof masses is symmetrically disposed and suspended from a substrate by spring structure. The thermally-actuated element is a line structure to effectively reduce the motional impedance and direct current power. Wherein, the thermally-actuated element is connected to the proof masses or the spring structure. The plurality of driving elements are respectively disposed on both sides of the thermally-actuated element to provide a driving current. When the driving current flows through the thermally-actuated element, the thermally-actuated element will be deformed and thus the proof masses will be driven to produce a harmonic oscillation.

Abstract: An ultra low power thermally-actuated oscillator and driving circuit thereof are provided. The ultra low power thermally-actuated oscillator includes proof masses, thermally-actuated element and a plurality of driving elements. The proof masses is symmetrically disposed and suspended from a substrate by spring structure. The thermally-actuated element is a line structure to effectively reduce the motional impedance and direct current power. Wherein, the thermally-actuated element is connected to the proof masses or the spring structure. The plurality of driving elements are respectively disposed on both sides of the thermally-actuated element to provide a driving current. When the driving current flows through the thermally-actuated element, the thermally-actuated element will be deformed and thus the proof masses will be driven to produce a harmonic oscillation.

Abstract: A method for making a micro-electro-mechanical systems (MEMS) vibrating structure is disclosed. The MEMS is supported by a MEMS anchor system and includes a single-crystal piezoelectric thin-film layer that has a specific non-standard crystal orientation, which may be selected to increase an electromechanical coupling coefficient, decrease a temperature coefficient of frequency, or both. The MEMS vibrating structure may have dominant lateral vibrations or dominant thickness vibrations. The single-crystal piezoelectric thin-film layer may include Lithium Tantalate or Lithium Niobate, and may provide MEMS vibrating structures with precise sizes and shapes, which may provide high accuracy and enable fabrication of multiple resonators having different resonant frequencies on a single substrate.

Abstract: An active type temperature compensation resonator structure is provided, including a resonant body and a temperature compensation element embedded in the resonant body for a compensation current to pass therethrough. The temperature compensation element has a specified temperature coefficient of resistance that reflects the temperature of the resonant body. The magnitude of the compensated current corresponds to the reflected temperature of the resonant body. With the active type temperature compensation resonator structure, the temperature of the resonant body can be accurately reacted by the specified temperature coefficient of resistance, such that the temperature compensation element, through which the compensated current passes, can dynamically correspond to the temperature of the resonant body and accurately provide the resonant body with temperature compensation.

Abstract: This invention provides a micromechanical resonator oscillator structure and a driving method thereof. As power handling ability of a resonator is proportional to its equivalent stiffness, a better power handling capability is obtained by driving a micromechanical resonator oscillator at its high equivalent stiffness area. One of the embodiments of this invention is demonstrated by using a beam resonator. A 9.7-MHZ beam resonator via the high-equivalent stiffness area driven method shows better power handling capability and having lower phase noise.

Abstract: A MEMS resonator active temperature compensation method is provided. The MEMS resonator active temperature compensation method includes: a MEMS resonator is provided, wherein a structural resistance of the MEMS resonator is varied with an environmental temperature; a structural resistance shift value is formed by a variation of the environmental temperature; an electrical circuit is provided, wherein the electrical circuit is electrically connected with the MEMS resonator for providing an adjustment mechanism to the MEMS resonator; and a compensation value is provided from the adjustment mechanism for controlling the structural resistance shift value.

Abstract: A capacitively-driven Micro-Electro-Mechanical System (MEMS) resonator is provided, in which a piezoresistively differential measurement is used to enable the MEMS resonator to transfer a signal. The MEMS resonator uses a Complementary Metal-Oxide-Semiconductor (CMOS) manufacturing process to make its oscillator and piezoresistor to achieve electrical insulation, thereby lowering the level of feedthrough signal.

Abstract: A capacitively-driven Micro-Electro-Mechanical System (MEMS) resonator is provided, in which a piezoresistively differential measurement is used to enable the MEMS resonator to transfer a signal. The MEMS resonator uses a Complementary Metal-Oxide-Semiconductor (CMOS) manufacturing process to make its oscillator and piezoresistor to achieve electrical insulation, thereby lowering the level of feedthrough signal.