Patents by Inventor Vassili Kitch

Vassili Kitch 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: 7381638
    Abstract: First material (106) is situated on the surface of a substructure (100 and 102) and in an opening (104), such as a Wench, that extends partway through the substructure. Second material (108) is situated on the first material in the opening. A physical sputter etch is performed on the structure while it is in a sputter etch module (206) to remove the parts of the first material overlying the substructure's surface and situated above the opening and to remove part of the second material overlying the first material in the opening so that remaining parts of the first and second materials are situated in the opening. The so-modified structure is transferred from the sputter etch module under a substantial vacuum, normally via a transfer module (202), to a deposition module (203, 204, or 205) where a layer of third material is deposited over the substructure's surface and over the parts of the first and second materials in the opening.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: June 3, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6927160
    Abstract: A copper-containing layer suitable for an electrical interconnect in a device such as an integrated circuit is created by a procedure in which a trench (104) is formed through a dielectric layer (102) down to a substrate (100). A diffusion barrier (106) is provided over the dielectric layer and into the trench. Copper (108) is deposited over the diffusion barrier and into the trench. Chemical mechanical polishing is utilized to remove the copper outside the trench down substantially to the diffusion-barrier material overlying the dielectric layer. A sputter etch, typically of the reactive type, is then performed to substantially remove the diffusion-barrier material overlying the dielectric layer. The sputter etch typically removes copper above and/or in the trench at approximately the same rate as the diffusion-barrier material so as to substantially avoid the undesirable dishing phenomenon.
    Type: Grant
    Filed: May 13, 2002
    Date of Patent: August 9, 2005
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6602755
    Abstract: A bipolar transistor structure that includes a semiconductor material substrate that has a bottom substrate and base region of a first conductivity type and a buried layer, collector region and sink region of a second conductivity type. The substrate has an extrinsic base region of the first conductivity type and an emitter region of the second conductivity type, both of which extend from the substrate's upper surface into the base region. The bipolar transistor structure also includes a single patterned polysilicon layer with a first polysilicon portion of the first conductivity type in contact with the extrinsic base region and a second polysilicon portion of the second conductivity type in contact with the emitter region. The bipolar transistor structure is compact since contact to the extrinsic base region is made by the first polysilicon portion, which can be formed to a minimum dimension and self-aligned to the extrinsic base region.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: August 5, 2003
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6501180
    Abstract: In accordance with one embodiment of the invention, a diffusion barrier layer is formed in a copper interconnect structure by first forming a layer of intermetal dielectric material on an underlying layer of conductive material. A pattern of dual damascene structures is then formed in the interconnect dielectric layer. An adhesion layer is then formed on exposed sidewalls of the damascene structure and on the upper surface of the intermetal dielectric material. The adhesion-layer-lined dual damascene structures are then filled with a conductive material that includes copper. The copper-including conductive material is then planarized to the upper surface of the intermetal dielectric material. Intermetal dielectric material is then removed to expose the conductive material. A diffusion barrier material is then deposited on exposed surfaces of the conductive material.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: December 31, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6495904
    Abstract: A bipolar transistor structure that includes a semiconductor material substrate that has a bottom substrate and base region of a first conductivity type and a buried layer, collector region and sink region of a second conductivity type. The substrate has an extrinsic base region of the first conductivity type and an emitter region of the second conductivity type, both of which extend from the substrate's upper surface into the base region. The bipolar transistor structure also includes a single patterned polysilicon layer with a first polysilicon portion of the first conductivity type in contact with the extrinsic base region and a second polysilicon portion of the second conductivity type in contact with the emitter region. The bipolar transistor structure is compact since contact to the extrinsic base region is made by the first polysilicon portion, which can be formed to a minimum dimension and self-aligned to the extrinsic base region.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: December 17, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6413872
    Abstract: A technique is provided for laying out vias between metal layers in an integrated circuit structure utilizing conventional Metal n and Metal N+1 databases. A first database (Metal n) is created that defines a lower conductive layer. A second database (Metal N+1) is created that defines an upper conductive layer. Selected intersections of the first database and the second database are then determined, thereby creating a third database (via n) that defines a pattern of vias between the lower conductive layer and the upper conductive layer. This allows interconnect vias to be optimized in size and shape, thus providing lowest possible interlayer resistance, which in turn provides the best possible circuit performance and reliability.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: July 2, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6313000
    Abstract: A vertically-isolated bipolar transistor occupying reduced surface area is fabricated by circumscribing an expected active device region within a first narrow trench. The first trench is filled with sacrificial material impermeable to diffusion of conductivity-altering dopant, and then isolation dopant of a conductivity type opposite to that of the substrate is introduced into the trench-circumscribed silicon region. The introduced isolation dopant is then thermally driven into the substrate, with lateral diffusion of isolation dopant physically constrained by the existing first narrow trench. Epitaxial silicon is then formed over the substrate, with polysilicon formed in regions overlying the filled narrow trench. A second, wider trench encompassing the first trench is etched to consume epitaxial silicon, polysilicon, and the sacrificial material. The second trench is then filled with dielectric material.
    Type: Grant
    Filed: November 18, 1999
    Date of Patent: November 6, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6277726
    Abstract: A method for removing a resistive film formed on an electrode to increase the conductive contact area of the electrode positioned in a misaligned contact hole. The method comprises providing a substrate supporting an electrode layer. The electrode layer is etched to produce metal lines. During the processing of the metal lines, a resistive film is formed thereon. The resistive film is removed and a protective barrier is formed on the metal lines. A dielectric layer is formed on the substrate, including the metal lines. The dielectric layer is subsequently patterned to form contact holes or vias to expose a portion of the metal lines. The contact holes are filled with plugs such that a second electrode layer can be formed on the dielectric layer and the plugs.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: August 21, 2001
    Assignee: National Semiconductor Corporation
    Inventors: Vassili Kitch, Michael E. Thomas
  • Patent number: 6143641
    Abstract: In accordance with one embodiment of the invention, a diffusion barrier layer is formed in a copper interconnect structure by first forming a layer of intermetal dielectric material on an underlying layer of conductive material. A pattern of dual damascene structures is then formed in the interconnect dielectric layer. An adhesion layer is then formed on exposed sidewalls of the damascene structure and on the upper surface of the intermetal dielectric material. The adhesion-layer-lined dual damascene structures are then filled with a conductive material that includes copper. The copper-including conductive material is then planarized to the upper surface of the intermetal dielectric material. Intermetal dielectric material is then removed to expose the conductive material. A diffusion barrier material is then deposited on exposed surfaces of the conductive material.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: November 7, 2000
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6140238
    Abstract: A copper interconnect structure is formed in a semiconductor device using self-aligned copper or tungsten via pillars to connect upper and lower copper interconnect layers separated by a dielectric. The lower copper interconnect layer is formed on an underlying layer. The via pillars are formed on the lower copper interconnect layer. The copper upper interconnect layer is formed to make electrical contact to exposed upper surfaces of the via pillars.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: October 31, 2000
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch
  • Patent number: 6103629
    Abstract: A process for forming a via in a semiconductor device using a self-aligned tungsten pillar to connect upper and lower conductive layers separated by a dielectric. A Ti/TiN layer is formed on an underlying substrate layer, an aluminum-copper layer is formed on the Ti/TiN layer, a TiN layer is formed on the aluminum-copper layer and a tungsten layer is formed on the TiN layer. In one continuous etching step, the stack of tungsten, TiN, Al--Cu, Ti/TiN is then patterned and etched. A first dielectric is deposited overlying the exposed regions of the substrate layer and the conductive stack. The wafer is then planarized to expose the top of the tungsten layer. The wafer is again patterned and the tungsten is etched using the titanium nitride as an etch stop. A second dielectric is deposited to fill the resulting gaps and CMP processes are used to planarize the wafer and expose the top of the tungsten pillar.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: August 15, 2000
    Assignee: National Semiconductor Corporation
    Inventors: Vassili Kitch, Michael E. Thomas
  • Patent number: 5904569
    Abstract: A process for forming a via in a semiconductor device using a self-aligned metal pillar to connect metal layers separated by a dielectric. A first aluminum layer is formed on an oxide layer overlying a semiconductor substrate, a titanium nitride layer is formed on the aluminum layer and finally a second aluminum layer is formed on the titanium nitride layer. In one continuous etching step, the stack of aluminum/titanium nitride/aluminum is then patterned and etched. A first dielectric is deposited overlying the exposed regions of the oxide layer and the formed metal stack. The wafer is then planarized exposing the top of the second aluminum layer. The wafer is again patterned and the second layer of aluminum is etched using the titanium nitride as an etch stop. A second dielectric is deposited to fill the resulting gaps and CMP processes are used to planarize the wafer and expose the top of the aluminum pillar.
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: May 18, 1999
    Assignee: National Semiconductor Corporation
    Inventor: Vassili Kitch