Abstract: A semiconductor acceleration sensor, which prevents an adhesion of a movable portion to a fixed portion due to an electrostatic force generated during being handled. The acceleration sensor has a sensor portion and a handling portion. The sensor portion has a first semiconductor layer; a movable portion including a weight portion supported to the first semiconductor layer for moving in accordance with an acceleration externally applied thereto and movable electrodes integrally formed with the weight portion; and fixed electrodes having a detection surface confronted to a detection surface of the movable electrodes and supported to the first semiconductor layer. The handling portion is to be contacted during being handled, and is provided at surrounding portion of the sensor portion with a trench interposed therebetween. The sensor portion is electrically insulated from the handling portion by the trench.

Abstract: A structure and arrangement for improving the accuracy and efficiency of an angular rate sensing gyroscope is herein disclosed. Voltage pick-off conductors are applied to an area of the surface of a resonating element of an angular rate sensing gyroscope that is subject to substantially zero stress when the gyroscope is rotationally stationary. Actuator conductors are similarly applied to a resonating element at a location bounded by areas of the resonating element subject to substantially uniform levels of stress when the gyroscope is rotationally stationary. A method for improving the voltage response of a piezoelectric resonating element is also disclosed.

Abstract: An oscillator 20 and main frames 30-1 and 30-2, coupled to one another by beams 33-1 through 33-4, float above the upper face of a substrate 10. The main frames 30-1 and 30-2 are divided into a plurality of sections along a Y-axis. Drive electrode portions 51-1 through 51-4 drive the main frames 30-1 and 30-2 and the oscillator 20 in the direction of an X-axis. Due to an angular rate around a Z-axis perpendicular to the X and Y axes, the oscillator 20 oscillates in the direction of the Y-axis. The oscillation in the direction of the Y-axis is measured using a high-frequency signal applied to detection electrode portions 53-1 through 53-4, whereby the angular rate is detected. The main frame 30-1 is provided with drive electrode portions 51-1 and 51-2, while the main frame 30-2 is provided with drive electrode portions 51-3 and 51-4.

Abstract: A vehicle acceleration and attitude sensor is provided, having use as a vehicle collision sensor for activation of air bags and the like, and as well for detecting an unsafe angle or attitude of the vehicle. A compressible carrier medium of light or other wave energy, such as translucent foam, is coupled with a light or other wave energy source and a receiver. An inertial mass, which may consist of the carrier medium itself, is in contact with the carrier medium and operates to compress the carrier medium when the apparatus is either accelerated or tilted beyond a predetermined amount. A signal coupler and processor are associated with the energy source and receiver. The apparatus operates on the principle whereby compression of a scattering medium or an integrating cavity, within the region surrounding a light or other wave energy source, will increase the intensity of the wave energy. This increased intensity is translated into a measurement of the acceleration or tilt experienced by the sensor.

Abstract: Methods and apparatus for detecting particular frequencies of acoustic vibration utilize an electrostatically-tunable beam element having a stress-sensitive coating and means for providing electrostatic force to controllably deflect the beam element thereby changing its stiffness and its resonance frequency. It is then determined from the response of the electrostatically-tunable beam element to the acoustical vibration to which the beam is exposed whether or not a particular frequency or frequencies of acoustic vibration are detected.

Abstract: A densitometer using microwaves, which measures the density value of a to-be-measured substance in a to-be-measured liquid on the basis of a reception signal obtained by transmitting/receiving a microwave in/from the to-be-measured liquid by applicators, includes a clock source for generating a reference signal as a phase reference, an oscillator formed from a PLL circuit for generating a microwave having a frequency f in synchronism with the reference signal from the clock source, an oscillator formed from a PLL circuit for generating a microwave having a frequency f+&Dgr;f in synchronism with the reference signal from the clock source, a mixer for mixing the microwave from the oscillator, i.e.

Abstract: A micromechanical tuning fork gyroscope has an input axis out of the plane of the structure. In one embodiment, capacitor plates are provided in parallel strips beneath two apertured, planar proof masses suspended from a substrate by a support structure. The proof masses are paired and set in opposed vibrational motion by an electrostatic comb drive. In response to an input angular rate about the out-of-plane input axis, the proof masses translate with respect to the striped capacitors, thereby varying the capacitance between the capacitor strips and the proof masses as a function of the input rate. In another embodiment, proof mass combs of a comb drive are meshed between fixed drive combs which are electrically excited in pairs 180° out of phase.

Abstract: An angular accelerometer having a substrate, a plurality of fixed electrodes supported on the substrate and each including fixed capacitive plates, and a rotational inertia mass including a plurality of movable capacitive plates arranged to provide a capacitive coupling with the fixed capacitive plates. The rotational inertia mass is rotationally movable relative to the fixed electrodes in response to angular acceleration. The angular accelerometer further includes support members for supporting the rotational inertia mass and biasing the rotational inertia mass relative to the fixed electrodes during rotational movement of the rotational inertia mass.

Abstract: According to an example embodiment of the present invention, a semiconductor device having conductive structure is analyzed using acoustic energy. Acoustic energy is generated in the device, and a resulting acoustic wave is detected. Using the detected wave, an index of refraction of a portion of the conductive structure is determined as a function of the wave. The calculated index of refraction is used and at least one defect in the conductive structure is detected. Using this method, defects can be detected during or after the manufacture of semiconductor devices in a cost effective, reliable manner. This method is particularly useful for defects that are not detectable using typical optical scanning methods due to opaque material in semiconductor devices.

Abstract: To achieve a drive-axis oscillation with improved frequency and amplitude stability, additional feedback loops are used to adjust force-feedback loop parameters. An amplitude-control loop measures oscillation amplitude, compares this value to the desired level, and adjusts damping of the mechanical sense-element to grow or shrink oscillation amplitude as appropriate. A frequency-tuning loop measures the oscillation frequency, compares this value with a highly stable reference, and adjusts the gain in the force-feedback loop to keep the drive-axis oscillation frequency at the reference value. The combined topology simultaneously controls both amplitude and frequency. Advantages of the combined topology include improved stability, fast oscillation start-up, low power consumption, and excellent shock rejection.

Abstract: A microfabricated gyroscopic sensor for measuring rotation about a Z-axis. The sensor includes a substrate, a first mass, a second mass, a coupling system connecting the first mass and the second mass, and a suspension system connecting the first mass and the second mass to the substrate. The sensor further includes a drive system to cause the first mass and the second mass to vibrate in an antiphase mode along a drive axis, and a position sensor to measure a displacement of the first mass and the second mass along a sense axis perpendicular to the drive axis and generally parallel to the surface of the substrate, wherein rotation of the first mass and the second mass about the Z-axis perpendicular to the surface of the substrate and vibration of the first mass and the second mass along the drive axis generates a Coriolis force to vibrate the first mass and the second mass along the sense axis in antiphase to each other.

Abstract: There is provided a monitor and method for monitoring the condition of a photoresist film on a wafer in which the phase of high frequency ultrasonic pulses reflected from the wafer/photoresist interface provides an indication of the condition of the photoresist film.

Abstract: A high temperature, high pressure process seal is used with a process instrument having a control housing assembly with a 50 ohm control connection, and an elongate probe including a sensing element extending into a high temperature, high pressure process vessel. The probe has a process connection having a 50 ohm impedance. The seal operatively connects the probe to the control housing assembly. The seal includes an elongate cylindrical hollow seal adaptor receivable in an opening of the process vessel. An elongate shaft is coaxial with and extends through the adaptor and is adapted to connect the control connection to the process connection. A hard seal material between a select portion of the shaft and the adaptor is bonded to the shaft and the adaptor. Radial spacing between the shaft and the adaptor is greater at the select portion to provide a 50 ohm feed-through from the control connection to the process connection.

Abstract: A micromechanical gradient sensor having a substrate, a ring body which is mounted elastically above the substrate with the assistance of a first spring device, a driving device which is connected to the ring body for driving the ring body to rotary motions about the ring axis, and an acceleration sensing device which is secured to the ring body via a second spring device. The acceleration sensing device is designed in such a manner that, as a result of the centrifugal force acting due to the rotary motions, and as a result of the force acting against the spring tension of the two spring devices due to the gravitational acceleration, the acceleration sensing device is able to travel out along the sensor axis connecting it, and running through the ring axis. Also included is an evaluation unit for determining the excursion of the acceleration sensing device and for determining the angle of inclination of sensor axis relative to the perpendicular component.

Abstract: The present invention aims to present an angular velocity sensor having a self diagnosis function. An angular velocity sensor of the present invention includes a driving part for stably vibrating a driving part of a sensor element having a driver part and a detector part for detecting an angular velocity and detection means for detecting the angular velocity of the sensor element and obtains a self diagnosis signal for a malfunction by detecting a mechanical coupling signal obtained at the detection means.

Abstract: A device for monitoring an acceleration sensor located in a vehicle and detecting an acceleration quantity that describes an acceleration acting upon the vehicle. The device includes an averaging device that is used to generate a mean value of the acceleration quantity for a definable period of time. The mean value is largely independent of driving maneuvers performed with the vehicle. The device also includes a monitoring device in which a comparison between the mean value of the acceleration quantity and a threshold value is carried out to monitor the acceleration sensor.

Abstract: A vibration gyro sensor is constructed as follows. Namely, a detecting piezoelectric/electrostrictive element 12, which detects displacement generated in a direction perpendicular to a direction of vibration of a vibrator 2 when the vibrator is rotated, is provided on a detecting section. The detecting section is constructed by an integrated fired product made of ceramics together with the vibrator 2 and a support base 4. The detecting section is constructed by a first plate-shaped section 6 which is more thin-walled than the vibrator 2 and which has its principal surface extending in the direction of vibration. The piezoelectric/electrostrictive element 12 is formed in an integrated manner on the first plate-shaped section 6 in accordance with a film formation method.

Abstract: The invention provides an apparatus for measuring microgravity acceleration that includes an elongate flow chamber having a first end and a second end and a liquid contained therein. Each end of the chamber is engaged by a plug member that is positioned to block the flow of the liquid through the ends of the container. Each plug member is maintained at a different known temperature such that a temperature gradient is created across the flow chamber. Temperature sensors are immersed in the liquid, the sensors being spaced apart along a line intersecting the axis of the flow chamber and normal thereto. Quasi-steady components of acceleration can be calculated based on the difference in the temperatures measured by the temperature sensors.

Abstract: A gravity-type horizontal shift sensing apparatus being mounted on and moved along with an object for efficiently sensing and measuring any difference in angle of inclination of the object when the object moves. The apparatus includes two intersected rocking arms rotatably disposed between close-up inner cover and inner seat, and a weight suspended from the rocking arms. The rocking arm each is provided at one end outside the inner cover and the inner seat with a toothed wheel and an optical wheel associated with the toothed wheel. The toothed wheel meshes with a gear sideward projected from a wheel mounted to one side of the rocking arm. The wheel each also has an optical wheel associated therewith. Outer peripheries of the optical wheels on the rocking arms and the wheels respectively pass between two sensing elements mounted at two sides of recesses formed on the circuit board.

Abstract: The invention relates to an angular velocity sensor used in posture control of a moving element or navigation system, and is intended to realize higher sensitivity, lower offset, lower offset drift, lower translation acceleration sensitivity, and higher impact resistance in a small size and at low cost.