Patents by Inventor Ali A. Iranmanesh

Ali A. Iranmanesh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6177709
    Abstract: Method and apparatus are disclosed for a low power, high density cell based array structure that permits implementation of designs having compute/drive cell ratios of N:1. The improved performance is provided in part by relocating the substrate and well taps within the compute cell, and in at least some instances by removing the well tap from the drive cell. Further, an extra routing track may be provided by not sharing source/drain areas of adjacent drive cells.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: January 23, 2001
    Assignee: Synopsys, Inc.
    Inventor: Ali A. Iranmanesh
  • Patent number: 5682058
    Abstract: The present invention provides for an antifuse in an integrated circuit, which has a stacked antifuse structure on a first interconnection line. The stacked structure has a first programming layer of amorphous silicon on the first interconnection line, a very thin insulating layer of silicon dioxide on the first programming layer, and a second programming layer of amorphous silicon on the very thin oxide layer. A second interconnection line on the second programming layer completes the antifuse which has a low leakage current between the first and second interconnection lines.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: October 28, 1997
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali A. Iranmanesh
  • Patent number: 5663591
    Abstract: The present invention provides for a method of forming an antifuse in an integrated circuit having a first insulating layer on a semiconductor substrate.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: September 2, 1997
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali Iranmanesh
  • Patent number: 5661046
    Abstract: A BiCMOS method and device. The BiCMOS device achieves improved performance through the use of wrap-around silicide contacts, improved MOS gate formation, the use of n- and p-type LDD's, the formation of very shallow base regions in bipolar transistors, and through separate implants for base regions of the bipolar transistors and source/drains of the MOSFETS.
    Type: Grant
    Filed: August 4, 1994
    Date of Patent: August 26, 1997
    Assignee: National Semiconductor Corporation
    Inventors: Vida Ilderem, Ali A. Iranmanesh, Alan G. Solheim, Christopher S. Blair, Rick C. Jerome, Rajeeva Lahri, Madan Biswal
  • Patent number: 5627098
    Abstract: An antifuse structure in an integrated circuit including a first interconnection line, a second interconnection line formed over the first interconnection line, and a plurality of programming layers between the first and second interconnection lines. Each pair of programming layers has a metal layer therebetween which dissolves with the programming layers to form a conducting link during the programming of such antifuse structure. Such antifuse structure may also include a conductive plug between the programming layers and the second interconnection line.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: May 6, 1997
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali A. Iranmanesh
  • Patent number: 5589412
    Abstract: A series of self-aligned, intermediate strips of conductive material, which contact each of the drain regions in a corresponding number of columns of drain regions in a flash electrically programmable read-only-memory (EPROM), are formed as a thick layer of planarized polysilicon. By utilizing intermediate strips of conductive material which are formed from a thick layer of polysilicon, the formation of cracks or voids in the intermediate strips of conductive material can be eliminated.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: December 31, 1996
    Assignee: National Semiconductor Corporation
    Inventors: Ali Iranmanesh, John M. Pierce, Albert M. Bergemont
  • Patent number: 5587613
    Abstract: The present invention provides for an integrated circuit antifuse structure having a first metal interconnection line, a programing layer over the first interconnection line, an etch stop layer over the programming layer, a sacrificial buffer layer over the etch stop layer, an insulating layer over the buffer layer, and a second metal interconnection line over the insulating layer. An aperture extends through the insulating layer and the buffer layer. The buffer layer has etching characteristics which are different from those of the insulating layer and the etch stop layer. This permits the aperture through the insulating layer to be formed with substantially vertical sides and through the buffer layer to be formed with substantially sloped sides. The second interconnection line extends into the aperture to form an antifuse structure with a low capacitance and a consistent programming voltage.
    Type: Grant
    Filed: May 25, 1994
    Date of Patent: December 24, 1996
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali Iranmanesh
  • Patent number: 5572062
    Abstract: A method and resulting antifuse structure in an integrated circuit include a first metal interconnection layer on a first insulating layer over the substrate of the integrated circuit, a second insulating layer over the first metal interconnection layer. The second insulating layer has a via therein and a programming layer is located in the via. Such programming layer includes a first region on the first metal interconnection layer which is removed from sides of the second insulating layer in the via, and a second region on the sides of the second insulating layer via. The first region has substantially a first thickness, the second region has substantially a second thickness which is greater than the first thickness. Upon programming the antifuse structure, a conducting link forms in the first region of the programming layer.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: November 5, 1996
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali A. Iranmanesh
  • Patent number: 5572063
    Abstract: A bipolar transistor is provided in which the emitters do not traverse the base but terminate inside the top surface of the base. Each emitter is L-shaped in some embodiments. The base top surface has a polygonal or circular outer boundary. The transistor has a long emitter perimeter available for base current flow and more than two emitter sides (e.g., five sides) available for base current flow. Further, the transistor has a large ratio of the emitter area to the base area. Consequently, the transistor has low noise, high gain, high frequency range, and a small size.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: November 5, 1996
    Assignee: National Semiconductor Corporation
    Inventor: Ali A. Iranmanesh
  • Patent number: 5521440
    Abstract: An antifuse structure in an integrated circuit is provided. The antifuse structure has a first metal interconnection line and a first insulating layer over the first metal interconnection line. The first insulating layer has a via exposing a top surface of the first metal interconnection line. In the first aperture a metal plug contacts the first metal interconnection layer and has a top surface substantially coplanar with a top surface of the first insulating layer. A metal pad contacts and covers the top surface of the metal plug. The metal pad should be formed by a viscous barrier metal, such as TiW, to smooth the surface of the metal plug. A second insulating layer, relatively thin with respect to said first insulating layer, covers the metal pad and has an aperture exposing a top surface of the metal pad. A programming layer deposited over the second insulating layer and into the aperture contacts the top surface of metal pad. A second metal interconnection line rests on the programming layer.
    Type: Grant
    Filed: May 25, 1994
    Date of Patent: May 28, 1996
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali Iranmanesh
  • Patent number: 5514900
    Abstract: An antifuse structure in an integrated circuit including a first interconnection line, a second interconnection line formed over the first interconnection line, and a plurality of programming layers between the first and second interconnection lines. Each pair of programming layers has a metal layer therebetween which dissolves with the programming layers to form a conducting link during the programming of such antifuse structure. Such antifuse structure may also include a conductive plug between the programming layers and the second interconnection line.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: May 7, 1996
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali A. Iranmanesh
  • Patent number: 5512508
    Abstract: A method and apparatus for reducing interconnection capacitance. A lightly doped buried layer is provided in or on a substrate below a field oxide region. The capacitance of an interconnect on the field oxide is significantly reduced by the lightly doped buried layer. When using a p-type substrate, the lightly doped buried layer may, for example, be a lightly doped (10.sup.13 /cm.sup.3) n-type region. Junction capacitance of, for example, a bipolar transistor is also reduced.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: April 30, 1996
    Assignee: National Semiconductor Corporation
    Inventor: Ali A. Iranmanesh
  • Patent number: 5510629
    Abstract: A method and structure for an improved antifuse in an integrated circuit having a sacrificial layer under a programming layer which forces a conductive link upon programming to be formed away from corner regions of the via structures. The method includes the unique step of forming an improved aperture or via with sides through an inter dielectric layer where the antifuse is to be located. The improved aperture or via exposes a portion of a metal interconnection line through a portion of sacrificial layer located away from the inter dielectric layer sides. Such improved method of forming the antifuse also provides a superior antifuse structure.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: April 23, 1996
    Assignee: Crosspoint Solutions, Inc.
    Inventors: Yakov Karpovich, Ali A. Iranmanesh
  • Patent number: 5508552
    Abstract: A bipolar transistor is provided in which the base-emitter junctions do not traverse the base but terminate inside the top surface of the base. The transistor has long emitter perimeter available for current flow and more than two emitter sides (e.g., three sides) available for current flow, which allows obtaining a low base resistance, a low emitter resistance, a low collector resistance, a low base-collector capacitance, and a small size.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: April 16, 1996
    Assignee: National Semiconductor Corporation
    Inventors: Ali A. Iranmanesh, David E. Bien, Michael J. Grubisich
  • Patent number: 5440167
    Abstract: The present invention provides for a method of forming an antifuse in an integrated circuit having a first insulating layer on a semiconductor substrate. The method comprises forming a first metal interconnection layer on the first insulating layer; forming a programming layer on the first metal interconnection line; forming a relatively thin, second insulating layer over the programming layer; forming a first aperture through the second insulating layer where the antifuse is to be located to expose a portion of the programming layer; forming a barrier metal layer on the second insulating layer and in said first aperture to contact the portion of said programming layer; forming a relatively thick, third insulating layer on the barrier metal layer; forming a second aperture to expose a portion of the barrier metal layer; and forming a second metal interconnection layer on the third insulating layer and in the second aperture to contact the portion of the second barrier metal layer.
    Type: Grant
    Filed: February 23, 1994
    Date of Patent: August 8, 1995
    Assignee: Crosspoint Solutions, Inc.
    Inventor: Ali Iranmanesh
  • Patent number: 5436496
    Abstract: A vertical fuse structure including a lightly-doped shallow emitter 30 provides improved fusing characteristics. The structure includes a buried collector 14, an overlying base 30, and an emitter 44 above the base 30. In one preferred embodiment, the emitter 44 extends about 0.2 microns from the upper surface and has a dopant concentration of about 8.times.1019 atoms of arsenic per cubic centimeter at the surface. A lightly doped base region 30 extends for about 0.46 microns below the emitter 44 to the collector 14. The upper surface of emitter 44 includes a metal contact 60. Heating the metal 60/emitter 44 interface to its eutectic melting point using a current or voltage pulse causes the aluminum to short through the emitter 44 to the base 30. Shorting the emitter programs the fuse. A second preferred embodiment uses polysilicon as an interconnecting medium.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: July 25, 1995
    Assignee: National Semiconductor Corporation
    Inventors: Rick C. Jerome, Ronald P. Kovacs, George E. Ganschow, Lawrence K. C. Lam, James L. Bouknight, Frank Marazita, Brian McFarlane, Ali Iranmanesh
  • Patent number: 5399509
    Abstract: A semiconductor device and method to reduce the size of bipolar transistors and decrease the number of steps required to fabricate the bipolar transistor by using a unitary contiguous oxide sidewall to separate a collector contact from the base, emitter and emitter contact. The device and method may also be used during the fabrication of BiCMOS devices.
    Type: Grant
    Filed: February 1, 1993
    Date of Patent: March 21, 1995
    Assignee: National Semiconductor Corporation
    Inventor: Ali A. Iranmanesh
  • Patent number: 5389553
    Abstract: In a bipolar transistor, the collector and the base are formed in an isolation region laterally bounded by a field insulator. The isolation region corners are spaced far from the emitter to reduce the collector-emitter leakage current. The base does not extend laterally throughout the isolation region. Thus the base is small and the collector-base capacitance is small as a result. Those corners of the isolation region that are not covered by a base contact region are covered and contacted by an insulator. This insulator prevents the field insulator from being pulled back during wafer clean steps. Consequently, the field insulator does not expose the collector. Further, the insulator covering the corners prevents the metal silicide on the surface of the extrinsic base from contacting the corners. The insulator overlying the corners thus reduces the collector-base leakage current.
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: February 14, 1995
    Assignee: National Semiconductor Corporation
    Inventors: Michael J. Grubisich, Ali A. Iranmanesh
  • Patent number: 5389552
    Abstract: A bipolar transistor is provided in which the emitters do not traverse the base but terminate inside the top surface of the base. Each emitter is L-shaped in some embodiments. The base top surface has a polygonal or circular outer boundary. The transistor has a long emitter perimeter available for base current flow and more than two emitter sides (e.g., five sides) available for base current flow. Further, the transistor has a large ratio of the emitter area to the base area. Consequently, the transistor has low noise, high gain, high frequency range, and a small size.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: February 14, 1995
    Assignee: National Semiconductor Corporation
    Inventor: Ali A. Iranmanesh
  • Patent number: 5387813
    Abstract: A bipolar transistor is provided in which the base-emitter junctions do not traverse the base but terminate inside the top surface of the base. The transistor has long emitter perimeter available for current flow and more than two emitter sides (e.g., three sides) available for current flow, which allows obtaining a low base resistance, a low emitter resistance, a low collector resistance, a low base-collector capacitance, and a small size.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: February 7, 1995
    Assignee: National Semiconductor Corporation
    Inventors: Ali A. Iranmanesh, David E. Bien, Michael J. Grubisich