Patents by Inventor Ramesh Venugopal

Ramesh Venugopal 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: 8435849
    Abstract: A gate stack for an NMOS transistor in an IC to induce tensile stress in the NMOS channel is disclosed. The gate stack includes a first layer of undoped polysilicon, a second layer of n-type polysilicon to establish a desired work function in the gate, layer of compressively stressed metal, and a third layer of polysilicon to provide a silicon surface for subsequent formation of metal silicide. Candidates for the compressively stressed metal are TiN, TaN, W, and Mo. In a CMOS IC, the n-type polysilicon layer and metal layer are patterned in NMOS transistor areas, while the first polysilicon layer and third polysilicon layer are patterned in both NMOS and PMOS transistor areas. Polysilicon CMP may be used to reduce topography between the NMOS and PMOS gate stacks to facilitate gate pattern photolithography.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: May 7, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Xin Wang, Zhiqiang Wu, Ramesh Venugopal
  • Publication number: 20120190158
    Abstract: A gate stack for an NMOS transistor in an IC to induce tensile stress in the NMOS channel is disclosed. The gate stack includes a first layer of undoped polysilicon, a second layer of n-type polysilicon to establish a desired work function in the gate, layer of compressively stressed metal, and a third layer of polysilicon to provide a silicon surface for subsequent formation of metal silicide. Candidates for the compressively stressed metal are TiN, TaN, W, and Mo. In a CMOS IC, the n-type polysilicon layer and metal layer are patterned in NMOS transistor areas, while the first polysilicon layer and third polysilicon layer are patterned in both NMOS and PMOS transistor areas. Polysilicon CMP may be used to reduce topography between the NMOS and PMOS gate stacks to facilitate gate pattern photolithography.
    Type: Application
    Filed: April 5, 2012
    Publication date: July 26, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xin Wang, Zhiqiang Wu, Ramesh Venugopal
  • Publication number: 20110175168
    Abstract: A gate stack for an NMOS transistor in an IC to induce tensile stress in the NMOS channel is disclosed. The gate stack includes a first layer of undoped polysilicon, a second layer of n-type polysilicon to establish a desired work function in the gate, layer of compressively stressed metal, and a third layer of polysilicon to provide a silicon surface for subsequent formation of metal silicide. Candidates for the compressively stressed metal are TiN, TaN, W, and Mo. In a CMOS IC, the n-type polysilicon layer and metal layer are patterned in NMOS transistor areas, while the first polysilicon layer and third polysilicon layer are patterned in both NMOS and PMOS transistor areas. Polysilicon CMP may be used to reduce topography between the NMOS and PMOS gate stacks to facilitate gate pattern photolithography.
    Type: Application
    Filed: August 10, 2009
    Publication date: July 21, 2011
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xin WANG, Zhiqiang WU, Ramesh VENUGOPAL
  • Publication number: 20090152626
    Abstract: Shrinking dimensions of MOS transistors in integrated circuits requires tighter distributions of dopants in pocket regions from halo ion implant processes. In conventional fabrication process sequences, halo dopant distributions spread during source/drain anneals. The instant invention is a method of fabricating MOS transistors in an integrated circuit in which halo ion are performed after source/drain anneals. In the inventive method, source/drain spacers on MOS gate sidewalls are removed prior to halo ion implant processes. Spacers to offset metal silicide are formed after halo implants and may be of low-k dielectric material to reduce gate to drain capacitance. A compressive stress layer may be deposited on MOS gates after source/drain spacers are removed for greater stress transfer efficiency to the MOS gates. An integrated circuit embodying the inventive method is also disclosed.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 18, 2009
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Ramesh Venugopal, Srinivasan Chakravarthi, Chris Bowen
  • Publication number: 20090050980
    Abstract: A method of forming a semiconductor device with source/drain nitrogen implant, and related device. At least some of the illustrative embodiments are methods comprising forming a gate stack over a substrate, implanting a dopant species into an active region adjacent to the gate stack, and reducing a diffusivity of the dopant species by implanting nitrogen into the active region.
    Type: Application
    Filed: August 21, 2007
    Publication date: February 26, 2009
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Shashank S. EKBOTE, Srinivasan CHAKRAVARTHI, Ramesh VENUGOPAL
  • Publication number: 20080272442
    Abstract: The present invention facilitates semiconductor fabrication by providing methods of fabrication that employ high-k dielectric layers. An n-type well region (304) is formed within a semiconductor body (302). A threshold voltage adjustment implant is performed by implanting a p-type dopant into the n-type well region to form a counter doped region (307). A high-k dielectric layer (308) is formed over the device (300). A polysilicon layer (310) is formed on the high-k dielectric layer and doped n-type. The high-k dielectric layer (308) and the polysilicon layer (310) are patterned to form polysilicon gate structures. P-type source/drain regions (306) are formed within the n-type well region (304).
    Type: Application
    Filed: June 12, 2008
    Publication date: November 6, 2008
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Ramesh Venugopal, Christoph Wasshuber, David Barry Scott
  • Patent number: 7407850
    Abstract: The present invention facilitates semiconductor fabrication by providing methods of fabrication that employ high-k dielectric layers. An n-type well region (304) is formed within a semiconductor body (302). A threshold voltage adjustment implant is performed by implanting a p-type dopant into the n-type well region to form a counter doped region (307). A high-k dielectric layer (308) is formed over the device (300). A polysilicon layer (310) is formed on the high-k dielectric layer and doped n-type. The high-k dielectric layer (308) and the polysilicon layer (310) are patterned to form polysilicon gate structures. P-type source/drain regions (306) are formed within the n-type well region (304).
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: August 5, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Ramesh Venugopal, Christoph Wasshuber, David Barry Scott
  • Patent number: 7208379
    Abstract: A method for multiplying the pitch of a semiconductor device is disclosed. The method includes forming a patterned mask layer on a first layer, where the patterned mask layer has a first line width. The first layer can then be etched to form a first plurality of sloped sidewalls. After removing a portion of the patterned mask so that the patterned mask layer has a second line width less than the first line width, the first layer can be etched again to form a second plurality of sloped sidewalls. The patterned mask layer can then be removed. The first layer can be etched again to form a third plurality of sloped sidewalls. The first plurality of sloped sidewalls, the second plurality of sloped sidewalls, and the third plurality of sloped sidewalls can form an array of parallel triangular channels.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: April 24, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Ramesh Venugopal, Christoph Wasshuber
  • Publication number: 20060223248
    Abstract: The present invention facilitates semiconductor fabrication by providing methods of fabrication that employ high-k dielectric layers. An n-type well region (304) is formed within a semiconductor body (302). A threshold voltage adjustment implant is performed by implanting a p-type dopant into the n-type well region to form a counter doped region (307). A high-k dielectric layer (308) is formed over the device (300). A polysilicon layer (310) is formed on the high-k dielectric layer and doped n-type. The high-k dielectric layer (308) and the polysilicon layer (310) are patterned to form polysilicon gate structures. P-type source/drain regions (306) are formed within the n-type well region (304).
    Type: Application
    Filed: March 29, 2005
    Publication date: October 5, 2006
    Inventors: Ramesh Venugopal, Christoph Wasshuber, David Scott
  • Publication number: 20060113636
    Abstract: A method for multiplying the pitch of a semiconductor device is disclosed. The method includes forming a patterned mask layer on a first layer, where the patterned mask layer has a first line width. The first layer can then be etched to form a first plurality of sloped sidewalls. After removing a portion of the patterned mask so that the patterned mask layer has a second line width less than the first line width, the first layer can be etched again to form a second plurality of sloped sidewalls. The patterned mask layer can then be removed. The first layer can be etched again to form a third plurality of sloped sidewalls. The first plurality of sloped sidewalls, the second plurality of sloped sidewalls, and the third plurality of sloped sidewalls can form an array of parallel triangular channels.
    Type: Application
    Filed: November 29, 2004
    Publication date: June 1, 2006
    Inventors: Ramesh Venugopal, Christoph Wasshuber