Patents by Inventor Sunil V. Hattangady

Sunil V. Hattangady 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: 6956267
    Abstract: A method of fabricating a transistor includes providing a semiconductor substrate having a surface and forming a nitride layer outwardly of the surface of the substrate. The nitride layer is oxidized to form a nitrided silicon oxide layer comprising an oxide layer beneath the nitride layer. A high-K layer is deposited outwardly of the nitride layer, and a conductive layer is formed outwardly of the high-K layer. The conductive layer, the high-K layer, and the nitrided silicon oxide layer are etched and patterned to form a gate stack. Sidewall spacers are formed outwardly of the semiconductor substrate adjacent to the gate stack, and source/drain regions are formed in the semiconductor substrate adjacent to the sidewall spacers.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: October 18, 2005
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil V. Hattangady, Jaideep Mavoori, Che-Jen Hu, Rajesh B. Khamankar
  • Publication number: 20040159898
    Abstract: A method of fabricating a transistor includes providing a semiconductor substrate having a surface and forming a nitride layer outwardly of the surface of the substrate. The nitride layer is oxidized to form a nitrided silicon oxide layer comprising an oxide layer beneath the nitride layer. A high-K layer is deposited outwardly of the nitride layer, and a conductive layer is formed outwardly of the high-K layer. The conductive layer, the high-K layer, and the nitrided silicon oxide layer are etched and patterned to form a gate stack. Sidewall spacers are formed outwardly of the semiconductor substrate adjacent to the gate stack, and source/drain regions are formed in the semiconductor substrate adjacent to the sidewall spacers.
    Type: Application
    Filed: February 19, 2004
    Publication date: August 19, 2004
    Inventors: Sunil V. Hattangady, Jaideep Mavoori, Che-Jen Hu, Rajesh B. Khamankar
  • Patent number: 6716695
    Abstract: A method of fabricating a transistor includes providing a semiconductor substrate having a surface and forming a nitride layer outwardly of the surface of the substrate. The nitride layer is oxidized to form a nitrided silicon oxide layer comprising an oxide layer beneath the nitride layer. A high-K layer is deposited outwardly of the nitride layer, and a conductive layer is formed outwardly of the high-K layer. The conductive layer, the high-K layer, and the nitrided silicon oxide layer are etched and patterned to form a gate stack. Sidewall spacers are formed outwardly of the semiconductor substrate adjacent to the gate stack, and source/drain regions are formed in the semiconductor substrate adjacent to the sidewall spacers.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: April 6, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil V. Hattangady, Jaideep Mavoori, Che-Jen Hu, Rajesh B. Khamankar
  • Publication number: 20030143813
    Abstract: A semiconductor device and method for reducing dopant loss includes forming a gate electrode of an MOS transistor adjacent a semiconductor substrate. A relatively thin oxide screen layer is formed and disposed outwardly from the gate electrode. Nitrogen is then incorporated into the oxide screen layer. An upper dielectric layer is formed such that it is disposed outwardly from the nitrided oxide screen layer.
    Type: Application
    Filed: May 7, 2002
    Publication date: July 31, 2003
    Applicant: Texas Instruments Incorporated
    Inventors: Rajesh B. Khamankar, Amitabh Jain, Che-Jen Hu, Mark S. Rodder, Sunil V. Hattangady, Hiroaki Niimi, Zhiqiang Wu, Manoj Mehrotra
  • Publication number: 20020098712
    Abstract: Oxides of multiple thicknesses are made by selectively heating the wafer with a laser beam at the locations where enhanced oxide growth is desired.
    Type: Application
    Filed: October 18, 2001
    Publication date: July 25, 2002
    Inventors: Jaideep Mavoori, Douglas T. Grider, Sunil V. Hattangady, Douglas E. Mercer
  • Patent number: 6420729
    Abstract: A method of making a semiconductor device and the device. The device, according to a first embodiment, is fabricated by providing a silicon (111) surface, forming on the surface a dielectric layer of crystalline silicon nitride and forming an electrode layer on the dielectric layer of silicon nitride. The silicon (111) surface is cleaned and made atomically flat. The dielectric layer if formed of crystalline silicon nitride by placing the surface in an ammonia ambient at a pressure of from about 1×10−7 to about 1×10−5 Torr at a temperature of from about 850° C. to about 1000° C. The electrode layer is heavily doped silicon. According to a second embodiment, there is provided a silicon (111) surface on which is formed a first dielectric layer of crystalline silicon nitride having a thickness of about 2 monolayers.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: July 16, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Robert M. Wallace, Glen D. Wilk, Yi Wei, Sunil V. Hattangady
  • Patent number: 6399445
    Abstract: A method of fabricating a semiconductor MOS device and the device wherein there is initially provided a semiconductor substrate having a gate insulator layer thereon and intimate therewith. A region of one of a nitride or oxynitride is formed at the surface region of the layer remote from the substrate having sufficient nitride to act as a barrier against the migration of dopant therethrough to the substrate. A doped polysilicon gate or a metal gate is then formed over the region of a nitride or oxynitride. The amount of nitride in the insulator layer intimate and closely adjacent to the substrate is insufficient to materially alter the characteristics of the device being fabricated. The substrate is preferably silicon, the oxide and nitride are preferably those of silicon and the dopant preferably includes boron. The step of forming a region of one of a nitride or oxynitride includes the step of injecting neutral atomic nitrogen into the surface of the gate insulator layer surface remote from the substrate.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: June 4, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil V. Hattangady, Srikanth Krishnan, Robert Kraft
  • Patent number: 6331492
    Abstract: A method is disclosed for making gate oxides on a silicon wafer surface for multiple voltage applications comprising the steps of growing an oxide layer (12) on a wafer (10) surface, exposing the surface of the oxide layer (12) to a nitrogen ion containing plasma to form a nitrided layer (22). Next, a photoresist layer (14) is deposited over a portion of the oxide layer (12) and the isolation (30), followed by etching of the exposed nitrided layer 22 and a portion of the oxide layer (12) to create a thinner silicon dioxide layer (32). The photoresist layer (14) is removed, the wafer (10) is cleaned and then the thinner silicon dioxide layer (32) is removed prior to a final oxidation step to form a thinner silicon dioxide layer (34) having a different thickness than the silicon dioxide layer (12).
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: December 18, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: George R. Misium, Sunil V. Hattangady
  • Patent number: 6323114
    Abstract: An embodiment of the instant invention is a method of fabricating an electronic device over a semiconductor substrate which includes a dielectric layer formed between a first structure and a second structure, the method comprising the steps of: growing an oxide-containing layer (layer 204 of FIGS. 2a-2d) on the first structure (substrate 202 of FIGS. 2a-2d); forming a silicon-containing layer (layer 206 of FIG. 2b) on the oxide-containing layer; oxidizing substantially all of the silicon-containing layer by subjecting it to an ambient comprised of oxygen and nitrogen with a substrate temperature around 700 to 800 C.; and forming the second structure (layer 214 of FIG. 2d) on the oxidized silicon-containing layer. Preferably, the step of oxidizing substantially all of the silicon-containing layer is performed by subjecting the silicon-containing layer to an ambient containing: N2O with a wafer temperature around 700 to 800 C.; or NO with a wafer temperature around 700 to 800 C.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: November 27, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil V. Hattangady, Tad (Douglas) Grider, John W. Kuehne
  • Publication number: 20010021588
    Abstract: A method is disclosed for making gate oxides on a silicon wafer surface for multiple voltage applications comprising the steps of growing an oxide layer (12) on a wafer (10) surface, exposing the surface of the oxide layer (12) to a nitrogen ion containing plasma to form a nitrided layer (22). Next, a photoresist layer (14) is deposited over a portion of the oxide layer (12) and the isolation (30), followed by etching of the exposed nitrided layer 22 and a portion of the oxide layer (12) to create a thinner silicon dioxide layer (32). The photoresist layer (14) is removed, the wafer (10) is cleaned and then the thinner silicon dioxide layer (32) is removed prior to a final oxidation step to form a thinner silicon dioxide layer (34) having a different thickness than the silicon dioxide layer (12).
    Type: Application
    Filed: December 18, 1998
    Publication date: September 13, 2001
    Inventors: GEORGE R. MISIUM, SUNIL V. HATTANGADY
  • Patent number: 6277681
    Abstract: A method of making a semiconductor device and the device. The device, according to a first embodiment, is fabricated by providing a silicon (111) surface, forming on the surface a dielectric layer of crystalline silicon nitride and forming an electrode layer on the dielectric layer of silicon nitride. The silicon (111) surface is cleaned and made atomically flat. The dielectric layer if formed of crystalline silicon nitride by placing the surface in an ammonia ambient at a pressure of from about 1×10−7 to about 1×10−5 Torr at a temperature of from about 850° C. to about 1000° C. The electrode layer is heavily doped silicon. According to a second embodiment, there is provided a silicon (111) surface on which is formed a first dielectric layer of crystalline silicon nitride having a thickness of about 2 monolayers.
    Type: Grant
    Filed: March 16, 1999
    Date of Patent: August 21, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Robert M. Wallace, Glen D. Wilk, Yi Wei, Sunil V. Hattangady
  • Patent number: 6268296
    Abstract: A method is disclosed for making gate oxides on a silicon wafer surface for multiple voltage applications comprising the steps of growing an oxide layer (12) on a wafer (10) surface. Next, a photoresist layer (14) is deposited over a portion of the oxide layer (12) and the isolation (30). The entire wafer (10) is exposed to a nitrogen ion containing plasma to form a nitrided layer (22). The photoresist (14) is removed, and the exposed portion of the oxide layer (12) is etched to the wafer (10) surface. Finally, an oxidation step forms a silicon dioxide layer (34) having a different thickness than the silicon dioxide layer (12).
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: July 31, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: George R. Misium, Sunil V. Hattangady
  • Patent number: 6261973
    Abstract: A method is disclosed of nitridating an oxide containing surface the disclosed method includes the steps of, obtaining a substrate, growing an oxide layer on the substrate, exposing the surface of the oxide layer to a nitrogen ion containing plasma at, e.g., room temperature, wherein the nitrogen ions form a nitrided layer on the oxide layer resistant to chemistries used to etch oxide.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: July 17, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: George R. Misium, Sunil V. Hattangady
  • Patent number: 6251761
    Abstract: A gate stack (104) including a gate dielectric with reduced effective electrical thickness. A high-k dielectric (108) is formed over the silicon substrate (102). Remote plasma nitridation of the high-k dielectric is performed to create a nitride layer (107) over the high-k dielectric (107). A conductive layer (110) is formed over the nitride layer (107) forming the gate electrode.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: June 26, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Mark S. Rodder, Sunil V. Hattangady
  • Publication number: 20010002709
    Abstract: A method of making a semiconductor device and the device. The device, according to a first embodiment, is fabricated by providing a silicon (111) surface, forming on the surface a dielectric layer of crystalline silicon nitride and forming an electrode layer on the dielectric layer of silicon nitride. The silicon (111) surface is cleaned and made atomically flat. The dielectric layer if formed of crystalline silicon nitride by placing the surface in an ammonia ambient at a pressure of from about 1×10−7 to about 1×10−5 Torr at a temperature of from about 850° C. to about 1000° C. The electrode layer is heavily doped silicon. According to a second embodiment, there is provided a silicon (111) surface on which is formed a first dielectric layer of crystalline silicon nitride having a thickness of about 2 monolayers.
    Type: Application
    Filed: December 27, 2000
    Publication date: June 7, 2001
    Inventors: Robert M. Wallace, Glen D. Wilk, Yi Wei, Sunil V. Hattangady
  • Patent number: 6140024
    Abstract: A method is disclosed of nitridating an oxide layer (12) to form a stop layer for selective etching of sacrificial layer comprising the steps of, obtaining a wafer (10), forming a gate (30) on the wafer (10), depositing an oxide layer (12) on the wafer (10) and the gate (30), exposing the surface of the oxide layer (12) to a nitrogen ion containing plasma at, e.g., room temperature, wherein the nitrogen ions form a nitrided layer (22) on the oxide layer (12). Next, a silicate layer (32) is deposited on the nitrided layer (22), planarized and patterned with photoresist (14) for etching. The contacts or vias are then formed through the silicate layer (32) by etching down to the nitrided layer (22) that acts as a stop layer, followed by a second etching step that removes the nitrided layer (22). The photoresist (14) is then stripped and the silicon oxide layer (12) etch down to the wafer (10).
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: October 31, 2000
    Assignee: Texas Instruments Incorporated
    Inventors: George R. Misium, Sunil V. Hattangady
  • Patent number: 6110842
    Abstract: A method for forming integrated circuits having multiple gate oxide thicknesses. A high density plasma is used for selective plasma nitridation to reduce the effective gate dielectric thickness in selected areas only. In one embodiment, a pattern (12) is formed over a substrate (10) and a high density plasma nitridation is used to form a thin nitride or oxynitride layer (18) on the surface of the substrate (10) . The pattern (12) is removed and oxidation takes place. The nitride (or oxynitride) layer (18) retards oxidation (20b), whereas, in the areas (20a) where the nitride (or oxynitride) layer (18) is not present, oxidation is not retarded. In another embodiment, a thermal oxide is grown. A pattern is then placed that exposes areas where a thinner effective gate oxide is desired. The high density plasma nitridation is performed converting a portion of the gate oxide to nitride or oxynitride. The effective thickness of the combined gate dielectric is reduced.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: August 29, 2000
    Assignee: Texas Instruments Incorporated
    Inventors: Yasutoshi Okuno, Sunil V. Hattangady
  • Patent number: 5989962
    Abstract: The invention comprises a method of forming a semiconductor device is provided where a first gate insulator layer 26 is formed on an outer surface of semiconductor substrate 24. A mask body 28 is formed to cover portions of the insulator layer 26. The exposed portions of the layer 26 are subjected to a nitridation process to form a nitride layer 30. A second oxidation process forms a thick gate oxide layer 32. The nitride layer 30 inhibits the growth of oxide resulting in a single integrated device having gate insulator layers having two different thicknesses such that high voltage and low voltage transistors can be formed on the same integrated circuit.
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: November 23, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Thomas C. Holloway, Sunil V. Hattangady
  • Patent number: 5970345
    Abstract: The invention comprises an integrated circuit having both low voltage and high voltage MOS transistors and a method for making the integrated circuit. In accordance with the method of making the integrated circuit, a first oxide layer is formed outwardly from a semiconductor substrate comprising a low voltage region and a high voltage region. A sacrificial layer is formed outwardly from the first oxide layer. The part of the sacrificial layer disposed outwardly from the low voltage region is removed to form an intermediate structure. The intermediate structure is selectively etched to remove the part of the first oxide layer disposed outwardly from the low voltage region. A second oxide layer is then formed comprising a first area disposed outwardly from the low voltage region and second area disposed outwardly from the high voltage region. The formation of the second oxide layer in the second area consumes the sacrificial layer.
    Type: Grant
    Filed: October 22, 1998
    Date of Patent: October 19, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil V. Hattangady, George R. Misium