With Means To Concentrate Stress Patents (Class 257/418)
  • Patent number: 6180989
    Abstract: A structure and method for creating an integrated circuit passivation structure comprising, a circuit, a dielectric, and metal plates over which an insulating layer is disposed that electrically isolates the circuit, and a discharge layer that is deposited to form the passivation structure that protects the circuit from electrostatic discharges caused by, e.g., a finger, is disclosed. The discharge layer additionally contains dopants selectively deposited to increase electrostatic discharge carrying capacity while maintaining overall sensing resolution.
    Type: Grant
    Filed: August 31, 1998
    Date of Patent: January 30, 2001
    Assignee: STMicroelectronics, Inc.
    Inventors: Frank R. Bryant, Danielle A. Thomas
  • Patent number: 6150681
    Abstract: A monolithic, integrated circuit sensor combining both a differential pressure sensor and a flow sensor on the same silicon chip. The integrated circuit has a diaphragm with a number of piezo-resistive elements placed on it in the normal manner for a pressure sensor. In addition, a channel is provided between the spaces on the two sides of the diaphragm. The channel has a cross-section which is a fraction of the size of the diaphragm. In one embodiment, the channel is a hole in the diaphragm. In another embodiment, the channel is an etched groove in the frame supporting the diaphragm.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: November 21, 2000
    Assignee: Silicon Microstructures, Inc.
    Inventor: Henry V. Allen
  • Patent number: 6118164
    Abstract: A method of forming apparatus including a force transducer on a silicon substrate having an upper surface, the silicon substrate including a dopant of one of the n-type or the p-type, the force transducer including a cavity having spaced end walls and a beam supported in the cavity, the beam extending between the end walls of the cavity, the method including the steps of: (a) implanting in the substrate a layer of a dopant of said one of the n-type or the p-type; (b) depositing an epitaxial layer on the upper surface of the substrate, the epitaxial layer including a dopant of the other of the n-type or the p-type; (c) implanting a pair of spaced sinkers through the epitaxial layer and into electrical connection with said layer, each of the sinkers including a dopant of the one of the n-type or the p-type; (d) anodizing the substrate to form porous silicon of the sinkers and the layer; (e) oxidizing the porous silicon to form silicon dioxide; and (f) etching the silicon dioxide to form the cavity and beam.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: September 12, 2000
    Assignee: SSI Technologies, Inc.
    Inventors: James D. Seefeldt, Michael F. Mattes
  • Patent number: 6104073
    Abstract: The acceleration sensor is formed in a monocrystalline silicon wafer forming part of a dedicated SOI substrate presenting a first and second monocrystalline silicon wafer separated by an insulting layer having an air gap. A well is formed in the second wafer over the air gap and is subsequently trenched up to the air gap to release the monocrystalline silicon mass forming the movable mass of the sensor; the movable mass has two numbers of movable electrodes facing respective pluralities of fixed electrodes. In the idle condition, each movable electrode is separated by different distances from the two fixed electrodes facing the movable electrode.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: August 15, 2000
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Paolo Ferrari, Mario Foroni, Benedetto Vigna, Flavio Villa
  • Patent number: 6051866
    Abstract: A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: April 18, 2000
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Kevin A. Shaw, Z. Lisa Zhang, Noel C. MacDonald
  • Patent number: 6043524
    Abstract: A sensor (100) includes a fixed gate field-effect transistor (138) that produces a quiescent signal (V.sub.QUIESC1) in a channel (336) when a control signal (V.sub.CONTROL) is applied to a source (332) of the FGFET. A movable gate field-effect transistor (MGFET) (108) produces a sense signal (V.sub.ACCEL) in a channel (316) in response to a physical condition of the sensor when the control signal is applied to a source (312) of the MGFET such that the sense signal is proportional to the quiescent signal. The difference between the currents in the FGFET and MGFET is amplified by a differential amplifier (230) to produce the output signal (V.sub.OUT) of the sensor. The difference between a reference signal (V.sub.RATIO) and the quiescent signal is amplified in an amplifier (206) to produce the control signal that adjusts the output signal to be proportional to the reference signal.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: March 28, 2000
    Assignee: Motorola, Inc.
    Inventors: Eric D. Joseph, Barun K. Kar
  • Patent number: 6028343
    Abstract: An integrated circuit and method are provided for sensing activity such as acceleration in a predetermined direction. The integrated released beam sensor preferably includes a switch detecting circuit region and a sensor switching region connected to and positioned adjacent the switch detecting circuit region. The sensor switching region preferably includes a fixed contact layer, remaining portions of a sacrificial layer on the fixed contact layer, and a floating contact on the remaining portions of the sacrificial layer and having only portions thereof directly overlying the fixed contact layer and in spaced relation therefrom in a normally open position and extending lengthwise generally transverse to the predetermined direction so that the floating contact contacts the fixed contact layer responsive to acceleration in the predetermined direction. The floating contact is preferably a released beam which is released by opening a window or removing unwanted portions of the sacrificial layer.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: February 22, 2000
    Assignee: STMicroelectronics, Inc.
    Inventors: Tsiu Chiu Chan, Melvin Joseph DeSilva
  • Patent number: 6011273
    Abstract: The present invention provides a thin-film semiconductor device suitable for an areal-pressure-distribution detector and the like. The thin-film semiconductor device according to the present invention comprises an insulating substrate 1, and element regions R being integrated and arranged on the substrate in the form of a matrix and each including a set of mutually connected electrode 2 and thin-film transistor 3. Each electrode 2 senses a signal voltage applied from above the element region R. Meanwhile, the thin-film transistor 3 are on/off-controlled in order and detect the signal voltage applied to the corresponding electrodes 2. In each element region, the surface level H1 of the sensitive region SR where the major part of the electrode 2 is formed is higher by .DELTA.H than the surface level H2 of the non-sensitive region NSR where the corresponding thin-film transistor 3 and a wiring pattern 9 are formed.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: January 4, 2000
    Assignee: Sony Corporation
    Inventors: Hiroaki Ichikawa, Hisashi Kadota
  • Patent number: 6005275
    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.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: December 21, 1999
    Assignee: Seiko Instruments Inc.
    Inventors: Masataka Shinogi, Yutaka Saitoh, Yoshifumi Yoshida, Hirofumi Harada, Kenji Katoh
  • Patent number: 5949119
    Abstract: A device having at least one element of a floating rigid microstructure element made of a structure layer(s) and a rigidity lining which increases its resistance to flexing and to torsion. The increased rigidity of the microstructure element allows the thickness and/or the width to be reduced, particularly of the structure layer(s) and hence allows an increase in the thermal resistance.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: September 7, 1999
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Michel Vilain
  • Patent number: 5932921
    Abstract: When a diaphragm portion of the pressure sensor or the like is fabricated, anisotropic etching is needed. This etching is carried out by electrochemically stopped etching. During this process, a voltage is applied to the diaphragm portion. A diode is connected between said diaphragm portion and an integrated circuit to prevent the voltage from being applied to the integrated circuit connected with the diaphragm portion. The diode is obtained by shorting the base and collector of a lateral p-n-p transistor to each other. A collector region is formed offset from immediately under a conductor pattern to prevent a parasitic MOS effect from producing a channel serving as a leakage current path. Further, a heavily doped n-type diffused region acting as a channel stopper is formed along the outer periphery of the collector region.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: August 3, 1999
    Assignee: Denso Corporation
    Inventors: Minekazu Sakai, Inao Toyoda, Nobukazu Oba
  • Patent number: 5914520
    Abstract: A micromechanical device contains, on a carrier or substrate (1, 10), a micromechanical region which is covered on the chip by a planar covering (D) arranged on the carrier. A method for the production of a micromechanical device of this type provides that a body is formed in which a first insulating layer (2, 11) is arranged on a carrier (1, 10) and a silicon layer (3, 12) is arranged over the insulating layer. The silicon layer (3, 12) is structured, openings (L, LS) being formed down to the first insulating layers. An insulating layer region (IS, 13) and a planar further layer (P, 14) are applied. The further layer (P, 14) is structured, openings being formed down to the insulating layer region (IS, 13), the insulating layer region and the regions of the first insulating layer which are situated underneath it are selectively etched, and a covering layer is applied over the further layer as a planar covering (D). The device can be mounted in a plastic housing without a clean room atmosphere.
    Type: Grant
    Filed: March 26, 1996
    Date of Patent: June 22, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Wolfgang Werner
  • Patent number: 5914507
    Abstract: A micromechanical device or microactuator based upon the piezoelectric, pyroelectric, and electrostrictive properties of ferroelectric thin film ceramic materials such as PZT. The microdevice has a device substrate and a deflectable component. The deflectable component is mounted for deflection on the device substrate and has a sensor/actuator. The sensor/actuator has first and second electrodes and a piezoelectric thin film disposed between the first and second electrodes. The thin film is preferably PZT. The sensor/actuator is disposed on a sensor/actuator substrate. The sensor/actuator substrate is formed of a material selected for being resistive to attack by hydrofluoric acid vapor. The invention also relates to a method for fabricating such micromechanical devices or microactuators.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: June 22, 1999
    Assignee: Regents of the University of Minnesota
    Inventors: Dennis L. Polla, Joon Han Kim
  • Patent number: 5903038
    Abstract: A semiconductor sensing device (10) for sensing a lateral acceleration includes a field effect transistor (132) fabricated along a sidewall (114) of a trench (112) formed in a substrate (11). A movable gate (12) overlies a channel region (138) of the field effect transistor (132). In response to a lateral acceleration perpendicular to the sidewall (114) of the trench (112), the movable gate (12) moves relative to the substrate (11) in a direction substantially perpendicular to the sidewall (114). The conductive state of the channel region (138) depends on the distance between the movable gate (12) and the channel region (138) and changes in response to the lateral acceleration Thus, the motion of the movable gate (12) modulates a current flowing in the field effect transistor (132). The lateral acceleration is sensed by sensing the current flowing in the field effect transistor (132).
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: May 11, 1999
    Assignee: Motorola, Inc.
    Inventors: Zuoying Lisa Zhang, Shang-Hui Larry Tu, Guang Xuan Li
  • Patent number: 5894144
    Abstract: In a semiconductor acceleration sensor, a weight and thin beam parts adjacent to the weight are formed on a substrate, a moving electrode is formed on the weight, and a fixed electrode is formed at a position of the other substrate opposed to the moving electrode. Both the electrodes come in contact with each other and conduct as a result of acceleration on the weight, whereby the semiconductor acceleration sensor operates. The fixed electrode or the moving electrode is formed with a projection toward the opposed electrode and the projection and the electrode come in contact with each other and conduct by action of acceleration with a predetermined spacing held between both the electrodes for preventing occurrence of chattering caused by the electrostatic attraction force between both the electrodes.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: April 13, 1999
    Assignees: Akebono Brake Industry Co., Ltd.,, Nihon Inter Electronic Corporation
    Inventors: Masatomo Mori, Takashi Kunimi, Masahiro Nezu, Tadao Matsunaga, Rokurou Naya, Shougo Suzuki
  • Patent number: 5889311
    Abstract: A semiconductor device comprises a semiconductor acceleration sensor having a cuboid-shaped cantilever cut from a semiconductor wafer, a detecting device disposed on the cantilever for detecting a displacement of the cantilever due to an acceleration force applied to the cantilever, and a supporter for supporting and fixing the cantilever at one end thereof.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: March 30, 1999
    Assignee: Seiko Instruments R&D Center Inc.
    Inventors: Masataka Shinogi, Yutaka Saitoh, Kenji Kato
  • Patent number: 5883419
    Abstract: A transistor in accordance with the invention comprises an ultra-thin Mo--C film functioning as a channel for an electron flow with two ends of the thin metal film functioning as source and drain terminals of the transistor, respectively; a piezoelectric film formed on the Mo--C film, for producing a force in accordance with an applied electric field provided by a gate voltage; and an electrode film formed on the piezoelectric film functioning as a gate of the transistor to which the gate voltage is applied to produce the applied electric field; and wherein a resistance of the Mo--C film between the source and drain terminals changes in accordance with the force produced in response to the applied gate voltage. This transistor can be used as an element of the three dimensional integrated circuit with a laminated structure.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: March 16, 1999
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seong-Jae Lee, Kyoung-Wan Park, Min-Cheol Shin
  • Patent number: 5883420
    Abstract: A sensor (10,30) is formed that does not require a bonding process in an oxygen rich or vacuum ambient. In a first embodiment, a port (14), a channel (15) and an opening (18) are used to provide an oxidizing ambient to a cavity (13). During an oxidation process, the cavity (13) is sealed and any remaining oxidizing ambient is consumed to form a sealed cavity that is under a vacuum pressure. In an alternate embodiment, a cavity (32) is formed in a first substrate (31). The cavity (32) is covered by a second substrate (36) and an opening (33,34) is formed in the second substrate (36) above the cavity (32). These openings (33,34) allow an oxidizing ambient to enter the cavity (32).
    Type: Grant
    Filed: December 20, 1995
    Date of Patent: March 16, 1999
    Assignee: Motorola, Inc.
    Inventors: Andrew Mirza, Kenneth M. Seddon
  • Patent number: 5869876
    Abstract: A semiconductor strain sensor has a gauge forming region on a p-type substrate surrounded by a p-type isolation region that reaches the p-type substrate. The p-type substrate is etched so that the entire bottom surface of the gauge forming region is covered by the p-type substrate, and the p-type substrate or p-type isolation region is not exposed to the etched recess portion or isolation groove, each of which have a relatively high number of defects. Thus, leakage current at the PN junction can be decreased to decrease a variation in the potential of the gauge forming region.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: February 9, 1999
    Assignee: Denso Corporation
    Inventors: Seiichiro Ishio, Kenichi Ao, Hiroshige Sugito
  • Patent number: 5844287
    Abstract: An electronic fingerprint sensor works by the detection of pressure, the ridge lines of the finger exerting a greater pressure than the valleys. The sensor has a matrix of pressure microsensors and electronic control and signal-processing circuits. It is made in an entirely monolithic form, according to techniques for the making of electronic circuits (deposition of thin layers, photo-etching, doping and thermal processing), both for the pressure detection part and for the signal-processing and control part. The matrix-type pressure sensor uses either piezoelectric resistors lying on an insulator layer stretched above a cavity or a variable capacitor or a microcontactor.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: December 1, 1998
    Assignees: France Telecom, La Poste
    Inventors: Salman Abou Hassan, Marie-Josephe Revillet
  • Patent number: 5828115
    Abstract: A polysilicon ground plane is formed over dielectric layers and under a suspended, movable mass in a surface micromachined device. The process includes steps of forming a diffused region in a substrate, forming the dielectric layers over the substrate, forming the ground plane over dielectric layers, and forming a body having a suspended mass, a first anchor extending from the mass down to the diffused region, and a second anchor extending from the down to the ground plane. The two anchors are formed simultaneously. The ground plane, which can be formed with only three additional steps over prior processes, serves as a ground plane to control changes and also as a local interconnect.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: October 27, 1998
    Assignee: Analog Devices, Inc.
    Inventor: Theresa A. Core
  • Patent number: 5828116
    Abstract: The present invention provides an improved method of wire-bonding on a semiconductor chip, especially a small acceleration sensor chip which is mounted on a substrate with an adhesive having low stress characteristics such as a silicon resin. Further, the present invention provides a semiconductor device having a structure in which the improved method of wire bonding is easily applicable. The wire-bonding is performed by giving ultrasonic vibrations to the wires and the pads on which the wires are bonded while imposing pressure thereon. The vibration is given in a direction along a radial line extending from the center of the semiconductor chip.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: October 27, 1998
    Assignee: Denso Corporation
    Inventor: Kenichi Ao
  • Patent number: 5796152
    Abstract: A cantilever microstructure includes a cantilever arm with a proximal end connected to a substrate and a freely movable distal end. The cantilever arm comprises first and second sections and includes a continuous layer which exhibits a first thermal co-efficient of expansion (TCE). In one embodiment, an electrical contact is positioned at the distal end of the cantilever arm. A first layer is positioned on a surface of the continuous layer and along the first section thereof. The first layer exhibits a second TCE which is different from the first TCE of the continuous layer. A second layer is positioned on a surface of the continuous layer and along the second section thereof. The second layer exhibits a third TCE which is different from the first TCE of the continuous layer. Electrical control circuitry selectively applies signals to the first and second layers to cause a heating thereof and a flexure of the cantilever arm so as to bring the distal end thereof into contact with a conductive substrate.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: August 18, 1998
    Assignee: Roxburgh Ltd.
    Inventors: William N. Carr, Xi-qing Sun
  • Patent number: 5793073
    Abstract: A semiconductor thin film sensor device including a semiconductor body formed of silicon having a (110) plane; a depression formed by an anisotropic etch applied to a first surface of the semiconductor body, wherein the first surface is substantially parallel to the (110) plane; and a thin film insulation member having a predetermined configuration suspended over the depression, and having substantially opposing ends connected to the first surface of the semiconductor body so that the thin film insulation member is bridged across the depression. Preferably, the depth of the depression is over 200 .mu.m. In one embodiment, the predetermined configuration of the thin film insulation member is oriented substantially parallel to a <100> direction of the semiconductor body.
    Type: Grant
    Filed: March 1, 1996
    Date of Patent: August 11, 1998
    Assignee: Ricoh Co., Ltd.
    Inventors: Morimasa Kaminishi, Takayuki Yamaguchi, Yukito Satoh
  • Patent number: 5780885
    Abstract: Process for the production of accelerometers using the silicon on insulator method. The process comprises the following stages: a) producing a conductive monocrystalline silicon film on a silicon substrate and separated from the latter by an insulating layer; b) etching the silicon film and the insulating layer up to the substrate in order to fix the shape of the mobile elements and the measuring device; c) producing electric contacts for the measuring devices; d) partial elimination of the insulating layer in order to free the mobile elements, the remainder of the insulating layer rendering integral the substrate and the moving elements.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: July 14, 1998
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Bernard Diem, Marie-Therese Delaye
  • Patent number: 5770883
    Abstract: A pair of signal voltages outputted from a bridge circuit composed of plural strain gauges are linearly amplified individually by a pair of amplifiers, whereupon a difference between the pair of signal voltages is detected. The pair of amplifiers are formed respectively in regions that are symmetrical with each other on a chip. As a result, variations in the output characteristics between the amplifiers are decreased.
    Type: Grant
    Filed: September 19, 1996
    Date of Patent: June 23, 1998
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koki Mizuno, Hiroshi Okada, Inao Toyoda, Masakazu Kanosue, Yasutoshi Suzuki, Kenichi Yokoyama
  • Patent number: 5747858
    Abstract: An electronic component includes a substrate (11) having a device surface (13) and opposite ends (14, 15) adjacent to the device surface (13), an electronic device (16) supported by the device surface (13), and an interconnect substrate (30) overlying a first end (14) of the substrate (11) and electrically coupled to the electronic device (16). The electronic component can be manufactured by inserting the second end (15) of the substrate (11) into one of a plurality of holes (23) in a carrier (20) wherein the device surface (13) and the carrier (20) form an angle greater than approximately five degrees.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: May 5, 1998
    Assignee: Motorola, Inc.
    Inventor: George W. Hawkins
  • Patent number: 5723894
    Abstract: An electrical connection structure interconnects a first circuit member and a second circuit member and comprises a cantilever, a conductive needle, a terminal pad and a fixing element. The cantilever is formed in the semiconductor substrate and has an end remote from the semiconductor substrate. The conductive needle is at the end of the cantilever and is electrically connected to the first circuit member. The terminal pad is located on the second circuit member opposite the conductive needle tip when the first circuit member and the second circuit member are juxtaposed. The terminal pad is electrically connected to the second circuit member. The fixing element fixes the first circuit member juxtaposed to the second circuit member in a way that stresses the cantilever to apply a contact force between the conductive needle and the terminal pad.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: March 3, 1998
    Assignee: Hewlett-Packard Company
    Inventors: Toshiaki Ueno, Mitsuchika Saito
  • Patent number: 5682053
    Abstract: A simox wafer includes substrate (1), simox silicon dioxide layer (2) and monocrystalline simox silicon layer (3). An additional silicon nitride layer (5) is deposited on top of silicon layer (3) to allow the fabrication of a monocrystalline beam (4) by selectively etching the dioxide layer (2). The thermal insulating property of the resultant beam (4) offers an ideal site for construction of thermocouples (29), light modulators (60) and active components such as p-n diodes (34), MOS transistors (47) and bipolar transistors.
    Type: Grant
    Filed: January 18, 1996
    Date of Patent: October 28, 1997
    Assignee: AWA MicroElectronics Pty. Limited
    Inventor: Witold Wiszniewski
  • Patent number: 5677560
    Abstract: A micromechanical component having a carrier and a deformable element of a flat design disposed parallel to a surface of the carrier, with the deformable element being provided with a mechano-electric signal converter. The carrier and the deformable element are fabricated in one piece out of a semiconductor substrate and are electrically insulated from one another, with the insulation being obtained by a buried layer produced by ion implantation thereby providing a micromechanical component which is suitable for joint integration with electric circuits in CMOS technology.
    Type: Grant
    Filed: April 27, 1995
    Date of Patent: October 14, 1997
    Assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung e.V.
    Inventors: Gunther Zimmer, Wilfried Mokwa
  • Patent number: 5675176
    Abstract: A semiconductor device has a semiconductor substrate having a groove, and a semiconductor element formed in a surface region of the semiconductor substrate. A substance having a thermal expansion coefficient different from the semiconductor substrate is embedded in at least a portion of the groove, a crystal defect is generated from the region near the bottom of the groove in the semiconductor substrate, thereby alleviating stress and strain in other regions of the semiconductor substrate, such that such regions cannot generate crystal defects in a region necessary for a circuit operation of the semiconductor element of the surface region.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: October 7, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yukihiro Ushiku, Atsushi Yagishita, Satoshi Inaba, Minoru Takahashi, Masanori Numano, Yoshiki Hayashi, Yoshiaki Matsushita, Yasunori Okayama, Hiroyasu Kubota, Norihiko Tsuchiya
  • Patent number: 5659138
    Abstract: A surface type acceleration sensor includes a p-type single crystal silicon base plate, a cantilever functioning as a cantilever structure portion, and a plurality of strain gauges. The cantilever is disposed in a recess portion formed on the front face of the p-type single crystal silicon base plate so that the cantilever can be displaced in the upward and downward direction. The cantilever includes an epitaxial growth layer principally made of n-type single crystal silicon. The strain gauge is made of p-type silicon and formed on an upper face of the base end portion of the cantilever.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: August 19, 1997
    Assignee: Kabushiki Kaisha Tokai Rika Denki Seisakusho
    Inventors: Hitoshi Iwata, Makoto Murate
  • Patent number: 5637905
    Abstract: A high-temperature, integrated, pressure sensor includes a single crystal semiconductor substrate that is provided with a recess in a first surface thereof, the recess bounded by a rim. A first coil structure is positioned within the recess and a pressure diaphragm, comprising a single-crystal semiconductor wafer is bounded about its periphery to the rim of the semiconductor substrate. The bonding is created by a glass interlayer between the pressure diaphragm and the semiconductor substrate. A second coil structure is positioned on the underside of the pressure diaphragm and is separated from the first coil structure. Electrical circuitry is connected to both coil structures and provides an output indicative of changes in inductive coupling between the coils.
    Type: Grant
    Filed: February 1, 1996
    Date of Patent: June 10, 1997
    Assignee: New Jersey Institute of Technology
    Inventors: William N. Carr, Robert S. Okojie
  • Patent number: 5635739
    Abstract: A micromechanical accelerometer comprises a mass of monocrystalline silicon in which a substantially symmetrical plate attached to a silicon frame by flexible linkages is produced by selective etching. The plate has a plurality of apertures patterned and etched therethrough to speed further etching and freeing of the plate and flexible linkages, suspending them above a void etched beneath. The plate is capable of limited motion about an axis created by the flexible linkages. An accelerometer comprised of a substantially symmetrical, linkage supported plate configuration is implemented as an angular accelerometer paired with an auxiliary linear accelerometer, which is used to compensate for the linear sensitivity of the angular sensor, to achieve an instrument that is insensitive to linear acceleration and responds to angular acceleration.
    Type: Grant
    Filed: April 25, 1995
    Date of Patent: June 3, 1997
    Assignee: The Charles Stark Draper Laboratory, Inc.
    Inventors: Paul Grieff, Burton Boxenhorn, Marc S. Weinberg
  • Patent number: 5629538
    Abstract: A semiconductor chip, which is preferably designed as a pressure sensor, has on its rear side one or more depressions in which the pressure is measured by correspondingly designed diaphragms which are coupled to piezosensitive circuits. The surface of the depressions and, optionally, the rear side of the semiconductor chip are coated with a protective layer which ensures that the semiconductor is protected from aggressive media. The protective layer thereby makes it possible to use the sensor universally in acids, lyes or hot gases.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: May 13, 1997
    Assignee: Robert Bosch GmbH
    Inventors: Uwe Lipphardt, Guenther Findler, Horst Muenzel, Helmut Baumann
  • Patent number: 5627397
    Abstract: A semiconductor acceleration sensor according to the present invention performs acceleration detection by means of detecting increase or decrease in electrical current flowing between fixed electrodes formed on a semiconductor substrate taking a movable section in a movable state supported on the semiconductor substrate as a gate electrode. Two transistor structures are utilized in this detection. Current between fixed electrodes in one transistor structure increases when the movable section is subjected to acceleration and is displaced. At that time, current between fixed electrodes in the other transistor structure decreases. These two transistor structures are disposed proximately. By means of this proximate disposition, fluctuations in characteristics of both transistors are reduced, and by means of acceleration detection by differential type, temperature characteristics of the two transistors can be canceled favorably.
    Type: Grant
    Filed: March 13, 1995
    Date of Patent: May 6, 1997
    Assignee: Nippondenso Co., Ltd.
    Inventors: Kazuhiko Kano, Yukihiro Takeuchi, Takamoto Watanabe, Kenichi Ao, Masakazu Kanosue, Hirofumi Uenoyama, Kenichi Nara
  • Patent number: 5619050
    Abstract: A semiconductor acceleration sensor capable of reducing a leakage current and manufacturing method thereof is disclosed. A beam structure is disposed on a silicon substrate. The beam structure has a movable section, and the movable section is disposed spaced at a prescribed distance above silicon substrate. A movable electrode section is formed in one portion of movable section. Fixed electrodes made of an impurity diffusion layer are formed in silicon substrate to correspond to both sides of a movable electrode section. A peripheral circuit is formed in silicon substrate. The beam structure and the peripheral circuit are electrically connected by an electroconductive thin film, made of polysilicon. Then, when a voltage is applied to the beam structure, and a voltage is applied to both fixed electrodes, an inversion layer is formed, and an electrical current flows between the fixed electrodes.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: April 8, 1997
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hirofumi Uenoyama, Kenichi Ao, Masakazu Kanosue, Yasutoshi Suzuki, Yukihiro Takeuchi
  • Patent number: 5619046
    Abstract: The invention concerns a method of manufacturing a measuring device of the Fabry-P erot resonator type. The invention likewise concerns a measuring device manufactured by means of the method. The measuring device is particularly intended for measurement of the pressures inside engine cylinders and comprises a cavity and a first part and a second part, said two parts sandwiching the cavity between them. At least the first part, which consists of silicon, supports a spacer layer of silicon dioxide formed through thermal oxidation. The spacer layer which is partially removed through etching, is joined to the second part using the technique known as direct bonding (SDB).
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: April 8, 1997
    Assignee: AB Volvo
    Inventors: Olof Engstr om, Hans Richert
  • Patent number: 5616514
    Abstract: A micromechanical sensor includes a support of silicon substrate having an epitaxial layer of silicon applied on the silicon substrate. A part of the epitaxial layer is laid bare to form at least one micromechanical deflection part by an etching process. The bared deflection part is made of polycrystalline silicon which has grown in polycrystalline form during the epitaxial process over a silicon-oxide layer which has been removed by etching. In the support region and/or at the connection to the silicon substrate, the exposed deflection part passes into single crystal silicon. By large layer thicknesses, a large working capacity of the sensor is possible. The sensor structure provides enhanced mechanical stability, processability, and possibilities of shaping, and it can be integrated, in particular, in a bipolar process or mixed process (bipolar-CMOS, bipolar-CMOS-DMOS).
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: April 1, 1997
    Assignee: Robert Bosch GmbH
    Inventors: Joerg Muchow, Horst Muenzel, Michael Offenberg, Winfried Waldvogel
  • Patent number: 5614742
    Abstract: A high precision micromechanical accelerometer comprises a layered structure of five (5) semiconductor wafers insulated from one another by thin oxide layers. The accelerometer is formed by first connecting a coverplate and a baseplate to associated insulating plates. Counter-electrodes, produced by anisotropic etching from the respective insulating plates, are fixed to the coverplate and the baseplate respectively. The counter-electrodes are contactable through the cover or baseplate via contact windows. A central wafer contains a unilaterally linked mass (pendulum) that is also produced by anisotropic etching and which serves as a movable central electrode of a differential capacitor. The layered structure is hermetically sealed by semiconductor fusion bonding. A stepped gradation from the top is formed at a wafer edge region for attaching contact pads to individual wafers to permit electrical contacting of individual wafers. The invention permits fabrication of a .mu.
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: March 25, 1997
    Assignee: LITEF GmbH
    Inventors: Thomas Gessner, Martin Hafen, Eberhard Handrich, Peter Leinfelder, Bruno Ryrko, Egbert Vetter, Maik Wiemer
  • Patent number: 5610431
    Abstract: A cover for a micromechanical device through which input/output connections to the device are made. The cover includes at least two doped semiconductor standoffs supporting an insulative layer. One or more metalized vias extend from a top surface of the insulative layer, or from a bottom surface of the base, to a respective standoff. Electrical connection is made to the covered device through the metalized vias and doped semiconductor standoffs. The covered chip may be vacuum sealed by providing a ring-like standoff which borders the covered device when the cover is bonded to the base. The resulting covered chip is adaptable for various chip mounting techniques, including flip chip mounting, side mounting combined with either tape automated bonding (TAB) or conductive epoxy connections, or epoxy chip attachment with wire bonding connections. In one embodiment, conductive bumps are formed on the top surface of the insulative cover layer to accommodate flip chip mounting.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: March 11, 1997
    Assignee: The Charles Stark Draper Laboratory, Inc.
    Inventor: Jacob H. Martin
  • Patent number: 5604363
    Abstract: A less expensive small semiconductor pressure sensor in which a pressure sensing element is not displaced by vibration and the like and wire bonding is highly reliably effected includes a pressure sensing element having a diaphragm and a glass base die bonded to a die pad in substantially the same plane as that of an outer lead with a bonding resin. Each of two sets of hanging leads is attached to one of two opposite sides of the die pad to fix the die pad to a package base. With this arrangement, the die pad is securely bonded to the package base to prevent breakage of a metal wire caused by vibration and the like so that a less expensive and smaller semiconductor pressure sensor can be provided.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: February 18, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Motomi Ichihashi
  • Patent number: 5602411
    Abstract: A micromechanical component includes a fixed micromechanical structure having a pair of capacitor plates being formed of one or more conductive layers, and a movable micromechanical structure being formed of a dielectric layer to be introduced into or removed from an interstice between the plates. A capacitance change is obtained through the resilient or freely movable dielectric, so that the component can be inserted as a proportional or a non-proportional force sensor. A microsystem with an integrated circuit and a micromechanical component with a movable dielectric, as well as a production method for the component and the microsystem, are also provided.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: February 11, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventor: Thomas Zettler
  • Patent number: 5589703
    Abstract: An edge die bond semiconductor package including a semiconductor die having an active major surface and a mounting edge substantially orthogonal to the active surface, a base having a mounting surface, and material affixing the mounting edge of the semiconductor die to the mounting surface of the base.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: December 31, 1996
    Assignee: Motorola, Inc.
    Inventor: Ira E. Baskett
  • Patent number: 5587601
    Abstract: A pressure sensor assembly including semiconductor transducer elements disposed upon a diaphragm support structure, wherein the support structure is comprised of a plurality of substrate layers anodically bonded together. A groove is disposed in the support structure creating an area of reduced thickness within the support structure. The ares of reduced thickness acts as a stress concentration region. As such, the transducer elements are disposed within the ares of reduced thickness so as to efficiently monitor any deformations experienced by the support structure. The groove that creates the ares of reduced thickness is formed in each of the substrate layers, prior to bonding into the overall structure, as such a very accurately tolerance groove can be formed into the structure which greatly increases the reliability of the structure.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: December 24, 1996
    Assignee: Kulite Semiconductor Products, Inc.
    Inventor: Anthony D. Kurtz
  • Patent number: 5578843
    Abstract: Fabrication of semiconductor devices with movable structures includes local oxidation of a wafer and oxide removal to form a depression in an elevated bonding surface. A second wafer is fusion bonded to the elevated bonding surface and shaped to form a flexible membrane. An alternative fabrication technique forms a spacer having a depression on a first wafer and active regions on a second wafer, and fusion bonds the wafers together with the depression over the active regions. Devices formed are integrable with standard MOS devices and include FETs, capacitors, and sensors with movable membranes. An FET sensor has gate and drain coupled together and a drain-source voltage which depends on the gate's deflection. Selected operating current, channel length, and channel width provide a drain-source voltage linearly related to gate deflection.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: November 26, 1996
    Assignee: Kavlico Corporation
    Inventors: Raffi M. Garabedian, M. Salleh Ismail, Gary J. Pashby
  • Patent number: 5578845
    Abstract: A dielectric thin film device is constructed by a dielectric thin film using lead erbium zirconate titanate represented by (Pb.sub.1-y Er.sub.y) (Zr.sub.x Ti.sub.1-x)O.sub.3 with 0<x<1 and 0<y<1. This dielectric thin film element has excellent electric characteristics of a leak electric current and fatigue characteristics, etc. The dielectric thin film element may have a thermally grown silicon dioxide film, a titanium film, a platinum lower electrode, a film of lead erbium zirconate titanate represented by (Pb.sub.1-y Er.sub.y) (Zr.sub.x Ti.sub.1-x)O.sub.3 and a platinum upper electrode. These films and electrodes are sequentially formed on an n-type silicon substrate. In this case, 0.45.ltoreq.x.ltoreq.0.75 and 0.05.ltoreq.y.ltoreq.0.1 are set. A method for manufacturing a dielectric thin film has the steps of coating a substrate with a precursor solution of erbium lead zirconate titanate represented by (Pb.sub.1-y Er.sub.y) (Zr.sub.x Ti.sub.1-x)O.sub.
    Type: Grant
    Filed: June 22, 1994
    Date of Patent: November 26, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiyuki Masuda, Yasushi Ogimoto, Noboru Ootani
  • Patent number: 5576250
    Abstract: A process for the production of accelerometers using the silicon on insulator method. The process comprises the following stages: a) producing a conductive monocrystalline silicon film on a silicon substrate and separated from the latter by an insulating layer; b) etching the silicon film and the insulating layer up to the substrate in order to fix the shape of the mobile elements and the measuring devices; c) producing electric contacts for the measuring devices; d) partial elimination of the insulating layer in order to free the mobile elements, the remainder of the insulating layer rendering integral the substrate and the moving elements.
    Type: Grant
    Filed: December 27, 1993
    Date of Patent: November 19, 1996
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Bernard Diem, Marie-Therese Delaye
  • Patent number: 5572057
    Abstract: Adverse effects due to electrostatic force between a semiconductor substrate and a movable electrode are avoided with a new structure. A movable electrode of beam structure is disposed at a specified interval above a p-type silicon substrate. Fixed electrodes, each composed of an impurity diffusion layer, are disposed on both sides of the movable electrode on the p-type silicon substrate; these fixed electrodes are self-aligningly with respect to the movable electrode. The movable electrode is displaced in accompaniment to the action of acceleration, and acceleration is detected by change (fluctuation) in current between the fixed electrodes generated by means of this displacement. Additionally, an electrode for movable electrode upward-movement use is disposed above the movable electrode, a potential difference is given between the movable electrode and the electrode for movable electrode upward-movement use, and attractive force of the movable electrode to the silicon substrate is alleviated.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: November 5, 1996
    Assignee: Nippondenso Co., Ltd.
    Inventors: Toshimasa Yamamoto, Yukihiro Takeuchi, Yoshinori Ohtsuka, Kazuhiko Kano
  • Patent number: 5554875
    Abstract: A semiconductor device with a force and/or acceleration sensor (12), which has a spring-mass system (14, 16) responsive to the respective quantity to be measured and whose mass (16) bears via at least one resilient support element (14) on a semiconductor substrate (20). The semiconductor substrate (20) and the spring-mass system (14, 16) are integral components of a monocrystalline semiconductor crystal (10) with a IC-compatible structure. The three-dimensional structural form of the spring-mass system (12) is produced by anisotropic semiconductor etching, defined P/N junctions of the semiconductor layer arrangement functioning as etch stop means in order to more particularly create a gap (22) permitting respective movement of the mass (16) between the mass (16) and the semiconductor substrate (20).
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 10, 1996
    Assignee: Texas Instruments Deutschland
    Inventor: Siegbert Hartauer