Abstract:
A mechanical resonator having interconnected vibrating beams and counter balances whereby transfer of energy from the vibrating beams is essentially eliminated.
Abstract:
A miniature electrostatic capacitive sensor in which electrical insulation is reliably established between a CV conversion circuit and a sensing unit. Also disclosed is a manufacturing method for the above type of capacitive sensor. The capacitive sensor is constructed of a sensing unit having a movable electrode and a stationary electrode, and a CV-conversion-circuit-forming portion having a CV conversion circuit. The movable electrode is constructed of a first support portion, a leaf spring connected to the first support portion, and a mass portion movably supported by the leaf spring. The stationary electrode is formed of a second support portion and a projecting portion connected to the second support portion. The CV-conversion-circuit forming portion and the first and second support portion are made thin. Accordingly, a shallow clearance is formed between the CV-conversion-circuit forming portion and each of the first support portion and the stationary electrode. An insulating substance can thus be positively deposited in the clearance, thereby forming an electrically insulating portion between the CV conversion circuit and the sensing unit.
Abstract:
The present invention provides an acceleration sensor and an accelerometer having isolation structure formed using a bulk straight wall deep reactive ion etch process, whereby external stress sources are isolated from active accelerometer components.
Abstract:
Diamond microtip field emitters are used in diode and triode vacuum microelectronic devices, sensors and displays. Diamond diode and triode devices having integral anode and grid structures can be fabricated. Ultra-sharp tips are formed on the emitters in a fabrication process in which diamond is deposited into mold cavities in a two-step deposition sequence. During deposition of the diamond, the carbon graphite content is carefully controlled to enhance emission performance. The tips or the emitters are treated by post-fabrication processes to further enhance performance.
Abstract:
A method of manufacturing a semiconductor acceleration sensor comprises forming a strain sensing section on a surface of a semiconductor wafer, fixing the semiconductor wafer to a cooled fixing stage, cutting out a structural body having the strain sensing section from the semiconductor wafer, and connecting a support member to the structural body cut from the semiconductor wafer.
Abstract:
A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.
Abstract:
An accelerometer and sensor assemblies for medical implantable devices such as pacemakers, cardioverters, IPGs, PCDs, defibrillators, ICDs, and the like, includes at least one intermediate metallization layer sandwiched between a first lower surface of at least one upper sheet formed from a piezoelectric material surface, and a second upper surface of at least one lower sheet formed from a piezoelectric material. The at least one upper sheet has a first outer edge disposed between its first upper and first lower surfaces. The at least one lower sheet has a second outer edge disposed between its second upper and second lower surfaces. The at least one intermediate metallization layer is not disposed at all locations between the first lower surface and the second upper surface, but extends to an external region disposed between the first outer edge and the second outer edge, and is electrically connected to the external region. Various embodiments of the sensor or accelerometer are capable of providing high amplitude output signals and reducing parts and manufacturing costs.
Abstract:
A semiconductor device comprises a semiconductor acceleration sensor having a cantilever made of a semiconductor material, a supporter for supporting the cantilever, and diffused resistors disposed on the cantilever. An acceleration detecting device detects a displacement of the cantilever based on acceleration forces applied to the cantilever and on changes of resistance values of the diffused resistors.
Abstract:
A method is provided that may be used to design a family of capacitive microaccelerometers with different members of the family having different sensitivities to acceleration without having to make a radical design change to the basic construction. The microaccelerometer is a capacitively sensed angular motion micro-electromechanical system. The microaccelerometer includes a stationary plate electrode and a movable plate electrode substantially parallel with the stationary plate electrode. The movable plate electrode rotates through a dielectric fluid about an axis of rotation parallel to the stationary plate electrode in response to acceleration. The method includes determining the desired sensitivity and changing the stationary plate center of area relative to the movable plate so as to obtain the desired sensitivity.
Abstract:
A method is disclosed for integrating one or more microelectromechanical (MEM) devices with electronic circuitry on a common substrate. The MEM device can be fabricated within a substrate cavity and encapsulated with a sacrificial material. This allows the MEM device to be annealed and the substrate planarized prior to forming electronic circuitry on the substrate using a series of standard processing steps. After fabrication of the electronic circuitry, the electronic circuitry can be protected by a two-ply protection layer of titanium nitride (TiN) and tungsten (W) during an etch release process whereby the MEM device is released for operation by etching away a portion of a sacrificial material (e.g. silicon dioxide or a silicate glass) that encapsulates the MEM device. The etch release process is preferably performed using a mixture of hydrofluoric acid (HF) and hydrochloric acid (HCI) which reduces the time for releasing the MEM device compared to use of a buffered oxide etchant. After release of the MEM device, the TiN:W protection layer can be removed with a peroxide-based etchant without damaging the electronic circuitry.