Patents Examined by S. Mulpuri
  • Patent number: 5726089
    Abstract: A method for fabricating a semiconductor device having a bonded wafer structure capable of reducing crystal defect in a power element forming region thereof is disclosed A recess is formed in a control circuit element forming region of a first n- silicon substrate, then filled with a silicon oxide film and subjected to grinding and polishing to provide a mirror-surface. An n- epitaxial layer is formed on the surface of a second n+ silicon substrate, then the surface of the epitaxial layer is coupled to the surfaces of the silicon oxide film and second circuit region of the first substrate and heat-treated to be bonded thereto.
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: March 10, 1998
    Assignee: NEC Corporation
    Inventor: Kensuke Okonogi
  • Patent number: 5723379
    Abstract: A method for fabricating a polycrystalline silicon having a roughed surface, which is useful for a capacitor electrode is disclosed. The method is featured by depositing a polycrystalline silicon layer in such a manner that grains of silicon are caused at the surface of the polycrystalline silicon layer. The polycrystalline silicon layer thus obtained has a large effective area and is suitable for a capacitor electrode because of its increased effective surface area.
    Type: Grant
    Filed: January 6, 1994
    Date of Patent: March 3, 1998
    Assignee: NEC Corporation
    Inventors: Hirohito Watanabe, Toru Tatsumi
  • Patent number: 5721150
    Abstract: An apparatus and method wherein conductive patterns are written in amorphous silicon or polysilicon deposited on an integrated circuit and used for interconnecting circuit elements contained therein. The substantially pure amorphous silicon or polysilicon is deposited onto an integrated circuit face at low temperature. A Focused Ion Beam deposition system deposits dopant atoms into the deposited pure silicon in a desired pattern. The dopant atoms are then activated by heat from a focused laser beam which adiabatically anneals the specifically doped areas of the deposited silicon. The resulting annealed doped areas of the silicon have low resistance suitable for circuit conductors. The surrounding undoped silicon reins a high resistance and a good insulator.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: February 24, 1998
    Assignee: LSI Logic Corporation
    Inventor: Nicholas F. Pasch
  • Patent number: 5721162
    Abstract: A motion sensor including a sensing wafer with a bulk micromachined sensing element, and a capping wafer on which is formed the conditioning circuitry for the sensor. The sensing and capping wafers are configured such that, when bonded together, the capping wafer encloses the sensing element to form a monolithic sensor. The capping wafer is further configured to expose bond pads on the sensing wafer, and to enable singulation of the two-wafer stack into individual dies. Wire bonds can be made to both wafers, such that the sensor can be packaged in essentially any way desired.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: February 24, 1998
    Assignee: Delco Electronics Corporation
    Inventors: Peter James Schubert, Steven Edward Staller, Dan Wesley Chilcott, Mark Billings Kearney
  • Patent number: 5719073
    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: September 27, 1994
    Date of Patent: February 17, 1998
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Kevin A. Shaw, Z. Lisa Zhang, Noel C. MacDonald
  • Patent number: 5714404
    Abstract: A method for fabricating polycrystalline thin films on low-temperature (or high-temperature) substrates which uses processing temperatures that are low enough to avoid damage to the substrate, and then transiently heating select layers of the thin films with at least one pulse of a laser or other homogenized beam source. The pulse length is selected so that the layers of interest are transiently heated to a temperature which allows recrystallization and/or dopant activation while maintaining the substrate at a temperature which is sufficiently low to avoid damage to the substrate. This method is particularly applicable in the fabrication of solar cells.
    Type: Grant
    Filed: November 18, 1993
    Date of Patent: February 3, 1998
    Assignee: Regents of the University of California
    Inventors: Fred Mitlitsky, Joel B. Truher, James L. Kaschmitter, Nicholas J. Colella
  • Patent number: 5714415
    Abstract: A method of forming a thin semiconductor film including an impurity for obtaining a conductivity includes the step of depositing a thin amorphous silicon film by chemical vapor deposition using silane as a deposition source gas at a deposition rate of at least 3 nm/minute while introducing the impurity, and the step of crystallizing the deposited thin amorphous silicon film by annealing.
    Type: Grant
    Filed: January 29, 1996
    Date of Patent: February 3, 1998
    Assignee: NEC Corporation
    Inventor: Shizuo Oguro
  • Patent number: 5714395
    Abstract: The process includes the following steps: implantation of ions (12) in a semi-conducting wafer (10), to create a cleavage layer of gaseous microblisters (16) in the wafer, heat treatment of the wafer, in order to cause separation of a surface layer (18) from the rest of the wafer, along the layer of microblisters. According to the invention, the implantation is carried out at a depth equal to or greater than a given minimum depth so that the thin film obtained is rigid, and so that the heat treatment can release it.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: February 3, 1998
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Michel Bruel
  • Patent number: 5712181
    Abstract: A method for the formation of gate in a semiconductor device is disclosed. The method for the formation of gate in a semiconductor device, comprising the steps of: forming amorphous silicon and polysilicon over a gate insulating film atop a semiconductor substrate, in due order; implanting impurity ions into the polysilicon and carrying out heat treatment; and forming a layer of a refractory metal over the silicon and carrying out heat treatment, to form polycide. Capable of preventing the degradation which is attributed to the penetration of impurities and thermal instability when forming a P.sup.+ polygate, the method contribute to the improvement in electrical properties.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: January 27, 1998
    Assignee: LG Semicon Co., Ltd.
    Inventors: Jeong Soo Byun, Hyeong Joon Kim
  • Patent number: 5712177
    Abstract: An embodiment of the invention allows the reversing of the sequence of a stacked gate dielectric layer so that a thermal oxide overlies a CVD deposited oxide. A CVD dielectric (12) is first deposited to a desired thickness. Then a layer of silicon (16), either amorphous or polycrystalline, is deposited overlying the CVD dielectric, wherein this silicon layer is approximately one-half of the desired thickness of the final top oxide. The silicon layer is then thermally oxidized to form thermal oxide (18). This method of the invention allows the denser thermal oxide to be formed overlying the less dense CVD dielectric layer as desired to form a reverse dielectric stack.
    Type: Grant
    Filed: September 25, 1995
    Date of Patent: January 27, 1998
    Assignee: Motorola, Inc.
    Inventors: Vidya S. Kaushik, Hsing-Huang Tseng
  • Patent number: 5705406
    Abstract: A method for producing a semiconductor device having semiconductor layers of SiC with at least three doped layers on top of each other, comprises the steps of growing a first semiconductor layer of SiC; implanting an impurity dopant into the first layer to form a second doped surface layer as a sub-layer therein, the second doped surface layer being surrounded, except for the top surface thereof, by the first semiconductor layer; and epitaxially growing a third semiconductor layer of SiC on top of the second layer of SiC and regions of the first layer adjacent thereto to totally bury the second semiconductor layer. The impurity dopant implanted into the first semiconductor layer is of a first conductivity n or p type, and the first semiconductor layer being doped with a second, opposite conductivity type, so as to form a pn-junction at the interface between the first and second layers.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: January 6, 1998
    Assignee: ABB Research Ltd.
    Inventors: Kurt Rottner, Adolf Schoner, Nils Nordell
  • Patent number: 5702974
    Abstract: A method for fabricating a capacitor of a semiconductor device. The capacity of the capacitor is increased through enlargement of the surface area of storage electrode by providing a plurality of side walls which are of prominence and depression to a cylindrical storage electrode such that it can significantly contribute to the high integration of semiconductor devices.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: December 30, 1997
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Jeong Ho Kim
  • Patent number: 5700710
    Abstract: Crystal grains of a lower polysilicon layer is grown through an annealing or an ion-implantation before separation of the lower polysilicon layer into doped silicon pieces, an upper polysilicon layer with small crystal grains is deposited over the doped silicon pieces so as to wave at long intervals, and the upper polysilicon layer is roughened so as to wave at short intervals, thereby increasing the surface area of an accumulating electrode of a capacitor.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: December 23, 1997
    Assignee: NEC Corporation
    Inventor: Masanobu Zenke
  • Patent number: 5698456
    Abstract: A passivation structure is formed using two passivation layers and a protective overcoat layer using two masking steps. The first passivation layer is formed over the wafer and openings are provided to expose portions of the pads for testing the device and fusible links. After testing and laser repair, a second passivation layer is formed over the wafer followed a deposit of the protective overcoat. The protective overcoat is patterned and etched, exposing the pads. The remaining portions of the protective overcoat are used as a mask to remove portions of the second passivation layer overlying the pads. Leads are then attached to pads and the devices are encapsulated for packaging.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: December 16, 1997
    Assignee: SGS-Thomson Microelectronics, Inc.
    Inventors: Frank Randolph Bryant, Abha Rani Singh
  • Patent number: 5698453
    Abstract: A thin-film semiconductor pinhole component with monolithically integrated position-sensing photodetectors is herein referred to as a Position Sensitive Pinhole (PSP). Another embodiment is also discussed where a PSP is integrated onto a platform with controllable motion and is herein referred to as a Movable Position Sensitive Pinhole (MPSP). A third embodiment describes the MPSP with capacitive, electrostatic actuation incorporated into the device to achieve controlled motion, herein referred to as a Capacitively Actuated Movable Position Sensitive Pinhole (CAMPSP). Each of those embodiments of the present invention are discussed, as are their method of manufacture and use in a laser environment as a spatial filter.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: December 16, 1997
    Inventors: Evan D. H. Green, Tario M. Haniff, Albert K. Hu
  • Patent number: 5698458
    Abstract: A method of manufacture of a semiconductor device comprises forming a silicon dioxide film upon the surface of said device, forming patterns of silicon nitride upon the surface of said silicon dioxide film, ion implanting ions into said substrate adjacent to at least some of said silicon nitride patterns for well regions of a first polarity, forming a mask over said device, and deeply ion implanting with ions of opposite polarity into well regions of opposite polarity.
    Type: Grant
    Filed: July 15, 1996
    Date of Patent: December 16, 1997
    Assignee: United Microelectronics Corporation
    Inventors: Chen-Chiu Hsue, Sun-Chieh Chien, Chung-Yuan Lee, Ming-Tzong Yang
  • Patent number: 5696002
    Abstract: This is a system and method of forming an electrical contact to the optical coating of an infrared detector. The method may comprise: forming thermal isolation trenches 22 in a substrate 20; depositing a trench filler 24 in the thermal isolation trenches 22; depositing a common electrode layer 31 over the thermal isolation trenches 22; depositing an optical coating 26 above the common electrode layer 31; mechanically thinning the substrate to expose the trench filler 24; etching to remove the trench filler 24 in the bias contact area; depositing a contact metal 34 on the backside of the substrate 20, wherein the contact metal 34 connects to the common electrode layer 31 at bias contact areas 34 around a periphery of the thermal isolation trenches; and etching the contact metal 34 and the trench filler 24 to form pixel mesas of the contact metal 34 and the substrate 20. Bias contact vias 23 may be formed in the bias contact areas and then filled with bias contact metal 49.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: December 9, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Steven N. Frank, James F. Belcher, Charles E. Stanford, Robert A. Owen, Robert J. S. Kyle
  • Patent number: 5693505
    Abstract: The invention provides a method of fabricating a semiconductor device, including the steps of forming a plurality of active regions on a semiconductor substrate, covering a first active region with mask layers including a first mask layer and a second mask layer deposited on the first mask layer, implanting first electrically conductive type impurities into a second active region with the mask layers acting as a mask, removing the second mask layer, and implanting second electrically conductive type impurities into the first and second active regions. The method makes it possible to form a retrograde-distributed tripe well with less number of masks and less number of ion implantation than conventional methods.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: December 2, 1997
    Assignee: NEC Corporation
    Inventor: Migaku Kobayashi
  • Patent number: 5691212
    Abstract: This invention describes a new method for forming self-aligned silicide for application in MOSFET, and a new structure of MOSFET device featuring elevated source and drain, with the objectives of reducing silicide penetration into the source and drain junctions, of eliminating junction spikes, of obtaining smoother interface between the silicide and the silicon substrate, and of reducing the chance of bridging of the silicides on the gate and on the source and drain. The new structure is made by depositing an amorphous layer of silicon on a silicon substrate already patterned with field oxide, gate oxide, polysilicon gate, and silicon nitride spacer on the gate sidewalls. Novel oxide sidewall spacers are then created by first implanting nitrogen into the horizontal surface of the amorphous silicon layer and subsequently thermally oxidizing the part of the amorphous silicon on the vertical sidewalls that is not exposed to nitrogen implantation. A dopant implantation followed by an annealing at 600.degree. C.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: November 25, 1997
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chaochieh Tsai, Shun-Liang Hsu
  • Patent number: 5691211
    Abstract: Silicon is employed as a reducing agent in an acid bath to adsorb noble metals present as contaminants in the acid. In the manufacture of silicon devices for electronic memory and other devices, polonium-210 is adsorbed by silicon getters to reduce soft error rate attributable to alpha particle emissions from the radioactive polonium. The noble metals in addition to polonium which can be plated onto silicon using the disclosed method are gold, silver, platinum, copper, palladium, mercury, selenium and bismuth.
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: November 25, 1997
    Assignee: Micron Technology, Inc.
    Inventors: Troy Sorensen, Eric Grieger