Abstract: One embodiment of the present invention sets forth a serrated tooth actuator for driving MEMS resonator structures. The actuator includes a fixed drive electrode having a serrated tooth surface opposing a MEMS resonator arm also having a serrated tooth surface, where the MEMS resonator arm is configured to rotate towards the drive electrode when an AC signal is applied to the drive electrode. Such a configuration permits higher amplitude signals to be applied to the drive electrode without the performance of the actuator being compromised by nonlinear effects. In addition, the serrated tooth configuration enables a sufficiently high actuating force to be maintained even though the distance traversed by the MEMS resonator arm during operation is quite small. Further, the serrated configuration allows a MEMS resonator system to withstand larger fluctuations in voltage and larger substrate stresses without experiencing a substantial shift in resonant frequency.

Abstract: A piezoelectric vibrator has an airtight terminal including leads each having a plane portion. A vibrating piece includes a first part having a preselected thickness and a second part having a thickness smaller than the preselected thickness. The plane portion of each of the leads is connected to the second part of the vibrating piece. A case covers a periphery of the vibrating piece and is sealed on an outer circumference of the airtight terminal.

Abstract: In an electronic apparatus comprising a digital display portion and first and second oscillators comprising first and second oscillating circuits, each of the first and second oscillating circuits having a resonator, an amplifier, a plurality of capacitors, and at least one resistor, a mode of vibration of the resonator of the first oscillating circuit being the same as that of the resonator of the second oscillating circuit, an output signal being output from each of the first and second oscillating circuits, the output signal of one of the first and second oscillating circuits being a clock signal for use in operation of the electronic apparatus to display time information at the digital display portion.

Abstract: A highly reliable micro-resonator and communication apparatus is provided in which an influence on a substrate caused by an interaction generated by an oscillation between adjacent micro-resonant elements is eliminated. The micro-resonant element includes a plurality of micro-resonant elements using a micro-mechanical oscillation provided on the same substrate, in which a micro-resonant element to oscillate in a first phase and a micro-resonant element to oscillate in a second phase that is a reverse phase to the first phase are disposed to be a pair.

Abstract: A tuning fork resonator element that has a base portion, first and second resonating arms extending from the base portion in a first direction, and a support frame sandwiching the first and second resonating arms and being connected to the base portion includes: a first excitation electrode, formed in an area close to a connection portion with the base portion of the support frame, being connected to a mount electrode with a conductive adhesive; a second excitation electrode, formed in at least one of an area sandwiching the first and second resonating arms of the support frame and an area positioned farther than the first and second resonating arms in the first direction, being connected to a mount electrode with the conductive adhesive; and a cut portion of the support frame formed on an external surface of the support frame.

Abstract: A mechanical resonator is constructed such that it has a vibration body that performs a mechanical resonant vibration and also has an electrode located in the vicinity of the vibration body and such that it is shaped into the surface shape of the electrode when deformed during a resonance mode of the vibration body, whereby the electrostatic capacitance change per unit vibration displacement amount can be enlarged. In this way, a mechanical resonator can be realized which performs an effective electricity-to-machine or machine-to-electricity conversion. Moreover, this mechanical resonator can be used to realize a small-sized, high-performance filter circuit or switch circuit in a high-density integrated electrical circuit.

Abstract: There are many inventions described and illustrated herein. In one aspect, the present invention is directed to a temperature compensated microelectromechanical resonator as well as fabricating, manufacturing, providing and/or controlling microelectromechanical resonators having mechanical structures that include integrated heating and/or temperature sensing elements. In another aspect, the present invention is directed to fabricate, manufacture, provide and/or control microelectromechanical resonators having mechanical structures that are encapsulated using thin film or wafer level encapsulation techniques in a chamber, and including heating and/or temperature sensing elements disposed in the chamber, on the chamber and/or integrated within the mechanical structures. Other aspects of the inventions will be apparent from the detailed description and claims herein.

Abstract: A piezoelectric resonator element, comprises: a base made of a piezoelectric material; at least a pair of resonating arms provided in a unified manner with the base and extending in parallel with each other from the base; a portion defining a long groove provided to each of the resonating arms along a longitudinal direction; and a driving electrode provided to the long groove. Each of the resonating arms includes a structure to adjust hardness balance between right and left structures with respect to a virtual central line extending in the longitudinal direction.

Abstract: One embodiment of the present invention sets forth a serrated tooth actuator for driving MEMS resonator structures. The actuator includes a fixed drive electrode having a serrated tooth surface opposing a MEMS resonator arm also having a serrated tooth surface, where the MEMS resonator arm is configured to rotate towards the drive electrode when an AC signal is applied to the drive electrode. Such a configuration permits higher amplitude signals to be applied to the drive electrode without the performance of the actuator being compromised by nonlinear effects. In addition, the serrated tooth configuration enables a sufficiently high actuating force to be maintained even though the distance traversed by the MEMS resonator arm during operation is quite small. Further, the serrated configuration allows a MEMS resonator system to withstand larger fluctuations in voltage and larger substrate stresses without experiencing a substantial shift in resonant frequency.

Abstract: One embodiment of the present invention sets forth a serrated tooth actuator for driving MEMS resonator structures. The actuator includes a fixed drive electrode having a serrated tooth surface opposing a MEMS resonator arm also having a serrated tooth surface, where the MEMS resonator arm is configured to rotate towards the drive electrode when an AC signal is applied to the drive electrode. Such a configuration permits higher amplitude signals to be applied to the drive electrode without the performance of the actuator being compromised by nonlinear effects. In addition, the serrated tooth configuration enables a sufficiently high actuating force to be maintained even though the distance traversed by the MEMS resonator arm during operation is quite small. Further, the serrated configuration allows a MEMS resonator system to withstand larger fluctuations in voltage and larger substrate stresses without experiencing a substantial shift in resonant frequency.

Abstract: One embodiment of the present invention sets forth a serrated tooth actuator for driving MEMS resonator structures. The actuator includes a fixed drive electrode having a serrated tooth surface opposing a MEMS resonator arm also having a serrated tooth surface, where the MEMS resonator arm is configured to rotate towards the drive electrode when an AC signal is applied to the drive electrode. Such a configuration permits higher amplitude signals to be applied to the drive electrode without the performance of the actuator being compromised by nonlinear effects. In addition, the serrated tooth configuration enables a sufficiently high actuating force to be maintained even though the distance traversed by the MEMS resonator arm during operation is quite small. Further, the serrated configuration allows a MEMS resonator system to withstand larger fluctuations in voltage and larger substrate stresses without experiencing a substantial shift in resonant frequency.

Abstract: Thermally induced frequency variations in a micromechanical resonator are actively or passively mitigated by application of a compensating stiffness, or a compressive/tensile strain. Various composition materials may be selected according to their thermal expansion coefficient and used to form resonator components on a substrate. When exposed to temperature variations, the relative expansion of these composition materials creates a compensating stiffness, or a compressive/tensile strain.

Abstract: A tuning fork type piezoelectric vibrator is provided with vibrating arms which can improve shock resistance while suppressing a CI value to a small value. A first groove (base end side) and a second groove (tip side) extend along a longitudinal direction from a base end of the vibrating arm and are formed on at least one of a front surface or a back surface of the vibrating arms. Then, a ratio L2/L1 which is the ratio of a length L2 of the first groove to a length L1 from the base end of the vibrating arm to the tip of the second groove, is set between 0.35 and 0.65, and a ratio d/L1 which is the ratio of a space d between the first groove and the second groove to the length L1 from the base end of the vibrating arm to the tip of the second groove, is set between 0.010 and 0.016.

Abstract: A printed circuit board (PCB) including a notch filter, or other suitable filter, is implemented in a communication device for attenuating RFI in transmissions sent from the communication device. The filter includes filter line that runs between at least two conductor layers on the PCB, in a substantially repeating pattern, which maximizes the space available on each conductor layer for additional uses.

Abstract: There are many inventions described and illustrated herein, as well as many aspects and embodiments of those inventions. In one aspect, the present invention is directed to a resonator architecture including a plurality of in-plane vibration microelectromechanical resonators (for example, 2 or 4 resonators) that are mechanically coupled to provide, for example, a differential signal output. In one embodiment, the present invention includes four commonly shaped microelectromechanical tuning fork resonators (for example, tuning fork resonators having two or more rectangular-shaped or square-shaped tines). Each resonator is mechanically coupled to another resonator of the architecture. For example, each resonator of the architecture is mechanically coupled to another one of the resonators on one side or a corner of one of the sides. In this way, all of the resonators, when induced, vibrate at the same frequency.

Abstract: A method for modifying the resonance frequency of a micro-mechanical resonator, and resonators on which the method is practiced. A packaged resonator is trimmed by directing electromagnetic energy to the resonator through a transparent portion of the package. The removal of mass (by the energy) affects the resonance frequency of the resonator in a predictable manner. In some embodiments, the energy is sourced from a femtosecond laser. In some variations of the illustrative embodiment, the amount of mass to be removed is determined as a function of its location on the resonator. A mass-trimming map is developed that identifies a plurality of potential mass-trimming sites on the resonator. A site can be classified as a fine-tuning site or a coarse-tuning site as a function of the degree to which mass removal at those sites affects the resonance frequency. The sites can also be characterized as a function of their position relative to features of the resonator (e.g., nodal lines, etc.).

Abstract: There are many inventions described and illustrated herein. In one aspect, the present invention is directed to a temperature compensated microelectromechanical resonator as well as fabricating, manufacturing, providing and/or controlling microelectromechanical resonators having mechanical structures that include integrated heating and/or temperature sensing elements. In another aspect, the present invention is directed to fabricate, manufacture, provide and/or control microelectromechanical resonators having mechanical structures that are encapsulated using thin film or wafer level encapsulation techniques in a chamber, and including heating and/or temperature sensing elements disposed in the chamber, on the chamber and/or integrated within the mechanical structures. Other aspects of the inventions will be apparent from the detailed description and claims herein.

Abstract: There are many inventions described and illustrated herein. These inventions are directed to a method of fabricating a microelectromechanical resonator having an output frequency that may be adjusted, tuned, set, defined and/or selected whether before and/or after final packaging. In one aspect, the method of the present invention adjusts, tunes, sets, defines and/or selects the frequency of the microelectromechanical resonator by changing and/or removing material from the mechanical structure of the resonator by resistively heating (in a selective or non-selective manner) one or more elements and/or beams of the mechanical structure (for example, the moveable or expandable electrodes and/or frequency adjustment structures).

Abstract: Thermally induced frequency variations in a micromechanical resonator are actively or passively mitigated by application of a compensating stiffness, or a compressive/tensile strain. Various composition materials may be selected according to their thermal expansion coefficient and used to form resonator components on a substrate. When exposed to temperature variations, the relative expansion of these composition materials creates a compensating stiffness, or a compressive/tensile strain.

Abstract: An electronic apparatus comprises a display portion and a plurality of oscillators, one of which is a quartz crystal oscillator comprising: a quartz crystal oscillating circuit comprising; an amplification circuit and a feedback circuit. For example, the feedback circuit is constructed by a quartz crystal resonator comprising vibrational arms and a base portion, and having novel shape and electrode construction. Also, the quartz crystal resonator is housed in a package. In addition, from a relationship of an amplification rate of the amplification circuit and a feedback rate of the feedback circuit, an output signal of the quartz crystal oscillating circuit having an oscillation frequency of a fundamental mode of vibration for the quartz crystal resonator can be provided with a frequency of high stability.

Abstract: Disclosed are high frequency, vertical silicon bulk acoustic resonators. Resonator structures having a relatively large transduction areas fabricated using a HARPSS fabrication process provide for high frequency capacitive resonators with significantly low impedance values. Impedance values as low as a few kilo-Ohms to sub-kilo-Ohm and quality factors in the range of 20,000 to 90,000 in the VHF range have been achieved for a first thickness mode of fabricated vertical silicon bulk acoustic resonators. Resonant frequencies as high as 983 MHz have been demonstrated for higher third thickness modes of the vertical silicon bulk acoustic resonators.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least two quartz crystal oscillators. Also, each of two quartz crystal oscillators of the at least two oscillators comprises a quartz crystal oscillating circuit having an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a width-extensional mode quartz crystal resonator or a thickness shear mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: A method for modifying the resonance frequency of a micro-mechanical resonator, and resonators on which the method is practiced. A packaged resonator is trimmed by directing electromagnetic energy to the resonator through a transparent portion of the package. The removal of mass (by the energy) affects the resonance frequency of the resonator in a predictable manner. In some embodiments, the energy is sourced from a femtosecond laser. In some variations of the illustrative embodiment, the amount of mass to be removed is determined as a function of its location on the resonator. A mass-trimming map is developed that identifies a plurality of potential mass-trimming sites on the resonator. A site can be classified as a fine-tuning site or a coarse-tuning site as a function of the degree to which mass removal at those sites affects the resonance frequency. The sites can also be characterized as a function of their position relative to features of the resonator (e.g., nodal lines, etc.).

Abstract: A radio frequency (RF) filter includes a substrate, first and second dielectric layers formed on first and second portions of the substrate, a ground plane formed on a third portion of said substrate, a carbon nanotube array, and first and second electrodes. The third portion of the substrate includes, at least in part, the area between the first and second portions thereof. The carbon nanotube array is formed on a portion of said ground plane between the first and second dielectric layers. The first and second electrodes are formed on the first and second dielectric layers, such that an RF signal may be input to and output from the carbon nanotube array via the first and second signal guides. A third electrode is disposed over the carbon nanotube array and is used to voltage bias the array.

Abstract: There are many inventions described and illustrated herein. These inventions are directed to a method of fabricating a microelectromechanical resonator having an output frequency that may be adjusted, tuned, set, defined and/or selected whether before and/or after final packaging. In one aspect, the method of the present invention adjusts, tunes, sets, defines and/or selects the frequency of the microelectromechanical resonator by changing and/or removing material from the mechanical structure of the resonator by resistively heating (in a selective or non-selective manner) one or more elements and/or beams of the mechanical structure (for example, the moveable or expandable electrodes and/or frequency adjustment structures).

Abstract: Thermally induced frequency variations in a micromechanical resonator are actively or passively mitigated by application of a compensating stiffness, or a compressive/tensile strain. Various composition materials may be selected according to their thermal expansion coefficient and used to form resonator components on a substrate. When exposed to temperature variations, the relative expansion of these composition materials creates a compensating stiffness, or a compressive/tensile strain.

Abstract: A quartz crystal resonator has a quartz crystal tuning fork base and quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. Each of the quartz crystal tuning fork tines has opposite main surfaces, a groove formed in at least one of the main surfaces, and an electrode disposed in the groove formed in at least one of the main surfaces so that a merit value M1 of a fundamental mode of vibration of the quartz crystal tuning fork resonator is greater than a merit value M2 of a second overtone mode of vibration thereof. The merit values M1 and M2 are defined by the ratios Q1/r1 and Q2/r2, respectively, where Q1 and Q2 represent a quality factor of the fundamental mode of vibration and the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator and r1 and r2 represent a capacitance ratio of the fundamental mode of vibration and the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator.

Abstract: There are many inventions described and illustrated herein. In one aspect, the present invention is directed to a temperature compensated microelectromechanical resonator as well as fabricating, manufacturing, providing and/or controlling microelectromechanical resonators having mechanical structures that include integrated heating and/or temperature sensing elements. In another aspect, the present invention is directed to fabricate, manufacture, provide and/or control microelectromechanical resonators having mechanical structures that are encapsulated using thin film or wafer level encapsulation techniques in a chamber, and including heating and/or temperature sensing elements disposed in the chamber, on the chamber and/or integrated within the mechanical structures. Other aspects of the inventions will be apparent from the detailed description and claims herein.

Abstract: A piezoelectric vibration piece is provided including a pair of vibration arms that are formed of a piezoelectric material, and extend in a horizontal direction from a base section. Grooves with a bottom are provided in the vibration arms, and extend along the length direction of the corresponding vibration arm. Support sections are provided in such a manner to cross the groove in a width direction to integrally connect the material structuring the vibration arm separated by the groove in the width direction.

Abstract: Aspects of the invention can provide a tuning-fork type piezo-oscillator piece, whose package, in which the tuning-fork type piezo-oscillator piece is mounted, is protected from colliding with oscillating arms even though a physical shock is given onto the tuning-fork type piezo-oscillator piece, and a mounting method thereof. The tuning-fork type piezo-oscillator piece can include a tuning-fork type piezo-oscillator piece main body equipped with a plurality of oscillating arms, a short side part formed along a direction perpendicular to the longitudinal direction of the tuning-fork type piezo-oscillator piece main body and connected to the tuning-fork type piezo-oscillator piece main body, and a long side part formed along the longitudinal direction of the tuning-fork type piezo-oscillator piece main body, while starting from the short side part, and equipped with a shock-absorbing part.

Abstract: A thin film micromechanical resonator (resonator) having improved drive efficiency, a resonator gyro having improved sensitivity in detecting an angular velocity, and a navigation system and an automobile using the resonator gyro. The resonator includes a tuning fork structure made of a non-piezoelectric material, and a first electrode and a second electrode disposed respectively at the inner side and the outer side of the tuning fork arm. On the first and second electrodes, a first piezo film and a second piezo film are provided respectively, and a third electrode and a fourth are respectively provided electrode thereon. When an alternating voltage is applied to the third and fourth electrodes at the opposite phases each other, the tuning fork resonates in the direction perpendicular to the center line. The resonator gyro detects, at the sensing section which is formed of another electrodes and another piezo film, the Coriolis force generated in proportion to angular velocity given to the resonator.

Abstract: A microelectromechanical (MEMS) resonator with a vacuum-cavity is fabricated using polysilicon-enabled release methods. A vacuum-cavity surrounding the MEMS beam is formed by removing release material that surrounds the beam and sealing the resulting cavity under vacuum by depositing a layer of nitride over the structure. The vacuum-cavity MEMS resonators have cantilever beams, bridge beams or breathing-bar beams.

Abstract: A compact high-performance mechanical vibration filter which deals with high frequency band signals. Microcolumn beams as minute mechanical vibrators are used to increase a mechanical resonance frequency. The plural microcolumn beams are arranged in an array and a common detection electrode surrounds each microcolumn beam with prescribed gaps between them, thereby preventing an output signal from becoming weak. When some of the mechanical vibrators are restrained from vibrating, it is possible to monitor and remove a noise component generated in the output signal by direct electromagnetic coupling of an input signal.

Abstract: A tuning fork-type crystal vibrator is provided that has improved CI and shock resistance. The tuning fork-type crystal vibrator includes a tuning fork-shaped crystal element made of a pair of tuning fork arms having grooves in their principal surfaces, and a tuning fork base portion from which the pair of tuning fork arms extends, an outer shape of the tuning fork-shaped crystal element being processed by etching. The tuning fork-type crystal vibrator has a protrusion, formed due to anisotropy of said etching, on a +X surface of the lateral faces of the tuning fork-shaped crystal element, and a first slanted portion rising from a ?X direction in a +X direction formed in a tuning fork slit. A tip of the tuning fork slit on a principal surface side is shifted in +X direction from a center line bisecting the tuning fork-shaped crystal element in a width direction to a position at which tuning fork vibrations of the pair of tuning fork arms are balanced.

Abstract: A tuning fork type quartz crystal unit has a base and a pair of arms extending from respective ends of the base in a crystallographic Y direction of quartz crystal. Each of the arms comprises a first crystal member and a second crystal member which extend in the Y direction. The first crystal member and the second crystal member are joined to each other in a crystallographic YZ plane by a direct bonding such that the first crystal member and the second crystal member have respective crystallographic X directions oriented away from each other and extending parallel to each other. Each of the arms has excitation electrodes disposed respectively on a pair of exposed surfaces thereof which lie in the YZ plane. The direct bonding comprises, for example, a siloxane bond by which the first crystal member and the second crystal member are joined to each other.

Abstract: A quartz crystal unit has a quartz crystal tuning fork resonator capable of vibrating in a flexural mode of an inverse phase. The quartz crystal tuning fork resonator has a fundamental mode of vibration, a second overtone mode of vibration, a quartz crystal tuning fork base, and a plurality of quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. A merit value M2 for the second overtone mode of vibration of the quartz crystal tuning fork resonator is less than 30 so that the second overtone mode of vibration thereof is suppressed, the merit value M2 being defined by a ratio Q2/r2, where Q2 and r2 represent a quality factor and a capacitance ratio of the second overtone mode of vibration, respectively, of the quartz crystal tuning fork resonator capable of vibrating in the second overtone mode.

Abstract: An electronic apparatus has a display portion and quartz crystal oscillators having different modes of vibration. Each of the quartz crystal oscillators has a quartz crystal oscillating circuit having a quartz crystal resonator. The quartz crystal resonator of one of the quartz crystal oscillating circuits is a width-extensional mode quartz crystal resonator capable of vibrating in a width-extensional mode. The width-extensional mode quartz crystal resonator has a vibrational portion, connecting portions disposed at ends of the vibrational portion, supporting portions connected to the vibrational portion through the connecting portions, and electrodes disposed on upper and lower surfaces of the vibrational portion. The quartz crystal oscillating circuit having the width-extensional mode quartz crystal resonator outputs a clock signal for operating the electronic apparatus to display time information at the display portion.

Abstract: A mechanical oscillator is provided for use in micro-electromechanical systems (MEMS) for application in radio frequency filters and oscillators, motion and pressure sensors and other micro applications. The oscillator is of monolithic construction and has a high Q with little energy loss because of teeth attached to the oscillating member which contain energy and prevent losses.

Abstract: There is described a time base comprising a resonator (4) and an integrated electronic circuit (3) for driving the resonator into oscillation and for producing, in response to this oscillation, a signal having a determined frequency. The resonator is an integrated micromechanical tuning fork resonator (4) supported above a substrate (2) and adapted to oscillate in a plane substantially parallel to the substrate. The tuning fork resonator comprises a base member (5) extending substantially perpendicularly from the substrate, a free-standing oscillating structure (6) connected to the base member and including at least a first pair of substantially parallel fork tines (7, 8) and an electrode structure (9) disposed adjacent to the fork tines and connected to the integrated electronic circuit.

Abstract: [Problem] To provide a resonator piece, a resonator, an oscillator and an electronic device that can prevent in advance defects from arising in the electrodes and whose frequency characteristics of the resonator piece and CI value are stable.

Abstract: An electric signal fed into a line generates electric field in response to its frequency, and a resonator placed closely to the line and in a substantially vacuum condition not higher than 100 pascal is excited by electrostatic force of the electric field and vibrates. Detecting means converts mechanical vibrations of the resonator into a signal in another form than the electric signal, then it detects the vibrations. The foregoing structure allows the resonator to be a micro-body and to process properly a high-frequency input signal of MHz or GHz band. A tight space between an input side and an output side does not permit an electric signal fed into the line to couple directly to the output side, and the resonator downsized to a micro-body is not subject to viscosity of air.

Abstract: In a tuning-fork piezoelectric resonator element, a quartz wafer is subjected to wet etching such that the lengthwise, widthwise, and thickness directions of resonating arms are oriented corresponding to the Y-axis, X-axis, and Z-axis of quartz crystal, lengthwise grooves are provided on principal surfaces of the resonating arms so that the center lines thereof are placed offset in the -X-direction from the center lines of the resonating arms, thereby balancing the stiffness between the right and left portions in the widthwise direction of the resonating arms, and stabilizing bending of the resonating arms.

Abstract: A compact high-performance mechanical vibration filter which deals with high frequency band signals. Microcolumn beams as minute mechanical vibrators are used to increase a mechanical resonance frequency. The plural microcolumn beams are arranged in an array and a common detection electrode surrounds each microcolumn beam with prescribed gaps between them, thereby preventing an output signal from becoming weak. When some of the mechanical vibrators are restrained from vibrating, it is possible to monitor and remove a noise component generated in the output signal by direct electromagnetic coupling of an input signal.

Abstract: A first type of MEMS resonator adapted to be fabricated on a SOI wafer is provided. A second type of MEMS resonator that is fabricated using deep trench etching and occupies a small area of a semiconductor chip is taught. Overtone versions of the resonators that provide for differential input and output signal coupling are described. In particular resonators suited for differential coupling that are physically symmetric as judged from center points, and support anti-symmetric vibration modes are provided. Such resonators are robust against signal noise caused by jarring. The MEMS resonators taught by the present invention are suitable for replacing crystal oscillators, and allowing oscillators to be integrated on a semiconductor chip. An oscillator using the MEMS resonator is also provided.

Abstract: In a tuning-fork piezoelectric resonator element 14, a quartz wafer is subjected to wet etching such that the lengthwise, widthwise, and thickness directions of resonating arms 16a and 16b are oriented corresponding to the Y-axis, X-axis, and Z-axis of quartz crystal, lengthwise grooves 18a and 18b are provided on principal surfaces of the resonating arms so that the center lines C1 thereof are placed offset in the −X-direction from the center lines C2 of the resonating arms, thereby balancing the stiffness between the right and left portions in the widthwise direction of the resonating arms, and stabilizing bending of the resonating arms.

Abstract: An electric signal fed into a line generates electric field in response to its frequency, and a resonator placed closely to the line and in a substantially vacuum condition not higher than 100 pascal is excited by electrostatic force of the electric field and vibrates. Detecting means converts mechanical vibrations of the resonator into a signal in another form than the electric signal, then it detects the vibrations. The foregoing structure allows the resonator to be a micro-body and to process properly a high-frequency input signal of MHz or GHz band. A tight space between an input side and an output side does not permit an electric signal fed into the line to couple directly to the output side, and the resonator downsized to a micro-body is not subject to viscosity of air.

Abstract: MEMS resonators (100, 400, 500) include a source of material that is capable of sublimation (128, 130, 406, 408, 502, 504). Conductive pathways (132, 134, 402, 404, 502, 504) to the material are used to supply current of ohmically heat the material in order to cause the material to sublimate. The material may be located either on or in close proximity to a resonant member (114) of the resonator. By sublimating the material, the mass of the resonant member is either increased or decreased thereby altering the resonant frequency of the resonant member. The resonant member is preferably located in a recess that is capped by a cap (202) forming a vacuum enclosure, and the material capable of sublimation preferably comprises a material that serves to getter any residual gases in the vacuum enclosure.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least one quartz crystal oscillator. Also, the at least one oscillator comprises a quartz crystal oscillating circuit comprising an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a length-extensional mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.

Abstract: Microelectromechanical resonators that can be fabricated on a semiconductor die by processes normally used in fabricating microelectronics (e.g., CMOS) circuits are provided. The resonators comprises at least two vibratable members that are closely spaced relative to a wavelength associated with their vibrating frequency, and driven to vibrate one-half a vibration period out of phase with each other, i.e. to mirror each others motion. Driving the vibratable members as stated leads to destructive interference effects that suppress leakage of acoustic energy from the vibratable members into the die, and improve the Q-factor of the resonator. Vibratable members in the form of vibratable plates that are formed by deep anisotropic etching one or more trenches in the die are disclosed. Embodiments in which two sets of vibratable plates are spaced by ½ the aforementioned wavelength to further suppress acoustic energy leakage, and improve the Q-factor of the resonator are disclosed.

Abstract: The electronic apparatus comprises a display portion and a quartz crystal oscillator at least, and said electronic apparatus comprises at least two quartz crystal oscillators. Also, each of two quartz crystal oscillators of the at least two oscillators comprises a quartz crystal oscillating circuit having an amplification circuit and a feedback circuit. The feedback circuit is constructed by a flexural mode, quartz crystal tuning fork resonator or a width-extensional mode quartz crystal resonator or a thickness shear mode quartz crystal resonator and for example, the quartz crystal tuning fork resonator comprising tuning fork tines and tuning fork base that are formed integrally, is shown with novel shape and electrode construction. Also, the quartz crystal tuning fork resonator, capable of vibrating in a fundamental mode and having a high frequency stability can be provided with a small series resistance and a high quality factor, even when the tuning fork resonator is miniaturized.