Patents by Inventor Vida Ilderem

Vida Ilderem 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: 5338694
    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: March 9, 1992
    Date of Patent: August 16, 1994
    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: 5338696
    Abstract: A BiCMOS method and device. The BiCMOS device achieves improved performance through the use of wraparound 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: March 1, 1993
    Date of Patent: August 16, 1994
    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: 5242854
    Abstract: A high performance bipolar transistor and a method of fabrication. Base resistance is reduced by a self-aligned silicide formed in the single-crystal region of the extrinsic base, thereby eliminating the polysilicon to single-crystal contact resistance as well as shunting the resistance of the single-crystal extrinsic base region. Oxide from the sidewall of the polysilicon local interconnection is selectively removed prior to silicide formation. Therefore, selected sidewalls of the poly interconnect layer also becomes silicided. This results in significant reductions in resistance of the interconnection, particularly for submicron geometries. Improved techniques for forming field oxide regions and for forming base regions of bipolar transistors are also disclosed.
    Type: Grant
    Filed: May 7, 1992
    Date of Patent: September 7, 1993
    Assignee: National Semiconductor Corporation
    Inventors: Alan G. Solheim, Christopher S. Blair, Vida Ilderem, Ali A. Iranmanesh
  • Patent number: 5231042
    Abstract: A method for formation of silicide structures on a semiconductor device. Oxide sidewalls are formed upon and selectively removed from polysilicon contacts. Refractory metal is deposited and heated, unreacted metal is removed, leaving a metal silicide on selected polysilicon sidewalls.
    Type: Grant
    Filed: February 13, 1992
    Date of Patent: July 27, 1993
    Assignee: National Semiconductor Corporation
    Inventors: Vida Ilderem, Alan G. Solheim, Rick C Jerome
  • Patent number: 5139961
    Abstract: A high performance bipolar transistor and a method of fabrication. Base resistance is reduced by a self-aligned silicide formed in the single-crystal region of the extrinsic base, thereby eliminating the polysilicon to single-crystal contact resistance as well as shunting the resistance of the single-crystal extrinsic base region. Oxide from the sidewall of the polysilicon local interconnection is selectively removed prior to silicide formation. Therefore, selected sidewalls of the poly interconnect layer also becomes silicided. This results in significant reductions in resistance of the interconnection, particularly for sub-micron geometries. Improved techniques for forming field oxide regions and for forming base regions of bipolar transistors are also disclosed.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: August 18, 1992
    Assignee: National Semiconductor Corporation
    Inventors: Alan G. Solheim, Bamdad Bastani, James L. Bouknight, George E. Ganschow, Bancherd Delong, Rajeeva Lahri, Steve M. Leibiger, Christopher S. Blair, Rick C. Jerome, Madan Biswal, Tad Davies, Vida Ilderem, Ali A. Iranmanesh
  • Patent number: 5107321
    Abstract: A BiCMOS device is revealed. 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: April 2, 1990
    Date of Patent: April 21, 1992
    Assignee: National Semiconductor Corporation
    Inventors: Vida Ilderem, Alan G. Solheim, Rick C. Jerome
  • Patent number: 5079182
    Abstract: A well tap for a field effect device formed using a single polysilicon process and a silicide layer is provided. The polysilicon layer which makes contact to the well is doped the same way as the well but is doped opposite of the source or drain. The silicide layer is formed on the upper and sidewall surfaces of the source or drain, well tap, and gate contacts for a field effect device. The silicide layer extends from the sidewall silicide across the upper surface of the transistors and up to the sidewall oxide of the transistor gates. The structure makes it possible to eliminate laterally-spaced separate well taps used in previous devices. Elimination of the laterally-spaced well taps permits hgher packing density, and lowers buried layer-to-substrate capacitance.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: January 7, 1992
    Assignee: National Semiconductor Corporation
    Inventors: Vida Ilderem, Steven M. Leibiger
  • Patent number: 4957777
    Abstract: The selective or blanket deposition of titanium silicide using a Very Low Pressure Chemical Vapor Deposition process is described. Silane and titanium tetrachloride are used as the silicon and titanium sources, respectively. A thin polysilicon layer is deposited prior to the silicide deposition to promote the nucleation of titanium silicide. It is shown that selective deposition is possible by controlling the polysilicon and the titanium silicide deposition times. The resulting titanium silicide films have resistivities in the range of 15-25 micro-ohms-cm.
    Type: Grant
    Filed: October 12, 1989
    Date of Patent: September 18, 1990
    Assignee: Massachusetts Institute of Technology
    Inventors: Vida Ilderem, L. Rafael Reif, Prabha K. Tedrow
  • Patent number: 4668530
    Abstract: This invention relates to a process and apparatus for the Low Pressure Chemical Vapor Deposition (LPCVD) of polycrystalline refractory metal silicides, such as TiSi.sub.2, in a reactor. An oxidized Si wafer is loaded in the reactor. The reactor is pumped down to a pressure of about 10.sup.-7 Torr, or less. The Si substrate is heated to the predetermined deposition temperature of about 630.degree. C. while avoiding heating of the reactor walls. The reactor is then purged with an inert gas, such as nitrogen. Next, polysilicon is deposited on the wafer by introducing SiH.sub.4 into the reactor at a pressure in the order of 0.2 Torr. A layer of polycrystalline titanium silicide is then formed on the polysilicon layer by introducing reactants, such as TiCl.sub.4 and SiH.sub.4, into the reactor at depositon temperatures between about 650.degree. to 700.degree. C. and pressures of between about 50 to 460 m Torr.
    Type: Grant
    Filed: July 23, 1985
    Date of Patent: May 26, 1987
    Assignee: Massachusetts Institute of Technology
    Inventors: L. Rafael Reif, Prabha K. Tedrow, Vida Ilderem