1998 - Draper Laboratory

1997 Patents IssuedThe following pages contain a list of all patents issued by the U.S. Patent Officeto Draper engineers during the 1997 calendar year.Bernstein, Jonathan J.Patent #5596222 Date Issued: January 21, 1997Wafer of transducer chipsPatent #5684324 Date Issued: November 4 , 1997Acoustic transducer chipPatent #5693181 Date Issued: December 2, 1997Method of making transducer chips with grooves on the wafer for easyseparation of the chipsDisclosed is a wafer and a method of making a wafer containing aplurality of severable transducer chips, including a wafer; a plurality oftransducer chips formed on the wafer; and a grid of longitudinal andlatitudinal grooves in the wafer for separating the chips from each otherand enabling them to be easily, individually severed from the wafer, aswell as a transducer chip and a method of making it, having integralraised contacts adapted for a flip chip or beam lead interconnection, witha transducer formed on the chip; and a plurality of raised contactsintegrally formed with the chip and electrically interconnected with thetransducer.Fyler, Donald C.Patent #5624110 Date Issued: April 29, 1997Cut segment pick-up assemblyA segment pickup apparatus for handling material segments is disclosed.The apparatus includes a frame and at least one pair of picker assembliescoupled to the frame. Each of the picker assemblies includes a lineararray of carding elements, and each of the carding elements is resilientlycoupled to one of the picker assemblies and is positionable relative to theframe in a resting position and in a picking position. Each of the cardingelements includes a base portion and a linear array of substantiallyparallel, elongated, resilient needle-like elements extending from the baseportion to a distal tip. When a carding element is positioned in theresting position, the distal tips of that carding element lie above apicking plane, and when a carding element is positioned in the pickingposition, the distal tips of that carding element lie substantially in thepicking plane. The picker assemblies are disposed such that the cardingelements are arranged in pairs. In each pair, the needle-like elements ofone carding element slant toward a first direction and the needle-likeelements of the other carding element slant toward a second direction.The segment pickup apparatus further includes a carding actuator devicefor positioning pairs of carding elements in the resting position and in thepicking position, and also includes a picker actuator device fordisplacing the picker assemblies relative to the frame in the first directionand in the second direction.Greiff, PaulPatent #5605598 Date Issued: February 25, 1997Monolithic micromechanical vibrating beam accelerometer with trimmableresonant frequencyA monolithic, micromechanical vibrating beam accelerometer with atrimmable resonant frequency is fabricated from a silicon substrate thathas been selectively etched to provide a resonant structure suspendedover an etched pit. The resonant structure comprises an accelerationsensitivemass and at least two flexible elements having resonantfrequencies. Each of the flexible elements is disposed generally collinearwith at least one acceleration-sensitive axis of the accelerometer. One endof at least one of the flexible elements is attached to a tension relief beamfor providing stress relief of tensile forces created during the fabricationprocess. Mass support beams having a high aspect ratio support the massover the etched pit while allowing the mass to move freely in thedirection collinear with the flexible elements. Also disclosed is a methodfor fabricating such an accelerometer. Further disclosed is an alternativeembodiment of the aforementioned accelerometer characterized by a lowprofile, and alternative planar processing methods for fabrication of theseand other embodiments.Greiff, Paul; Antkowiak, Bernard M.Patent #5650568 Date Issued: July 22, 1997Gimballed vibrating wheel gyroscope having strain relief featuresA gimballed vibrating wheel gyroscope for detecting rotational rates ininertial space is disclosed. The gyroscope includes a support oriented ina first plane and a wheel assembly disposed over the support parallel tothe first plane. The wheel assembly is adapted for vibrating rotationallyat a predetermined frequency in the first plane and is responsive torotational rates about a coplanar input axis for providing an outputtorque about a coplanar output axis. The gyroscope also includes a postassembly extending between the support and the wheel assembly forsupporting the wheel assembly. The wheel assembly has an inner hub, anouter wheel, and spoke flexures extending between the inner hub and theouter wheel and being stiff along both the input and output axes. Aflexure is incorporated in the post assembly between the support and thewheel assembly inner hub and is relatively flexible along the output axisand relatively stiff along the input axis. Also provided is a singlesemiconductor crystal fabrication technique and a dissolved waferfabrication technique. In one embodiment, the gyroscope includes combdrive electrodes. Also described is a box-shaped strain relief structure foruse in the spoke flexures and additional strain relief features.Greiff, Paul; Boxenhorn, BurtonPatent #5635639 Date Issued: June 3, 1997Micromechanical tuning fork angular rate sensorA micromechanical tuning fork gyroscope includes a suspended structurecomprising at least first and second vibratable structures. Each vibratablestructure is energizable to vibrate laterally, within a first plane, along anaxis normal to the rotation-sensitive axis. The lateral or inplane vibrationof the first and second vibratable structures effects simultaneous verticalor rotational movement of at least a portion of the suspended structureupon the occurrence of angular rotation of the gyroscope about therotation-sensitive axis. Vertical or rotational movement of the suspendedstructure is sensed, and a voltage proportional to the movement isgenerated, for providing an indication of angular rate of rotation by thegyroscope.Greiff, Paul; Sohn, Jerome B.Patent #5646348 Date Issued: July 8, 1997Micromechanical sensor with a guard band electrode and fabrication techniquethereforAn electrostatically actuated micromechanical sensor having a guardband electrode for reducing the effect of transients associated with adielectric substrate of the sensor is disclosed. A proof mass, responsive toan input, is suspended over the substrate and one or more electrodes aredisposed on the substrate in electrostatic communication with the proofmass to sense the input acceleration and/or to torque the proof mass backto a null position. A guard band electrode is disposed over the dielectricsubstrate in overlapping relationship with the electrodes and maintainsthe surface of the substrate at a reference potential, thereby shielding the1997 Patents Issued1