Patents by Inventor Tom Lii

Tom Lii 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: 10134731
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PMD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Grant
    Filed: April 18, 2017
    Date of Patent: November 20, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Patent number: 9741624
    Abstract: An integrated circuit may be formed by removing source/drain spacers from offset spacers on sidewalls of MOS transistor gates, forming a contact etch stop layer (CESL) spacer layer on lateral surfaces of the MOS transistor gates, etching back the CESL spacer layer to form sloped CESL spacers on the lateral surfaces of the MOS transistor gates with heights of ¼ to ¾ of the MOS transistor gates, forming a CESL over the sloped CESL spacers, the MOS transistor gates and the intervening substrate, and forming a PMD layer over the CESL.
    Type: Grant
    Filed: June 27, 2016
    Date of Patent: August 22, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Publication number: 20170221895
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PMD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Application
    Filed: April 18, 2017
    Publication date: August 3, 2017
    Inventor: Tom Lii
  • Patent number: 9704720
    Abstract: An integrated circuit may be formed by forming a sacrificial silicon nitride feature. At least a portion of the sacrificial silicon nitride feature may be removed by placing the integrated circuit in a two-step oxidized layer etch tool and removing a surface layer of oxidized silicon from the sacrificial silicon nitride feature using a two-step etch process. The two-step etch process exposes the integrated circuits to reactants from a plasma source at a temperature less than 40° C. and subsequently heating the integrated circuit to 80° C. to 120° C. while in the two-step oxidized layer etch tool. While the integrated circuit is in the two-step oxidized layer etch tool, without exposing the integrated circuit to an ambient containing more than 1 torr of oxygen, at least a portion of the sacrificial silicon nitride feature is removed using fluorine-containing etch reagents, substantially free of ammonia.
    Type: Grant
    Filed: August 4, 2016
    Date of Patent: July 11, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Tom Lii, David Farber
  • Patent number: 9659935
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PMD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: May 23, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Publication number: 20160343581
    Abstract: An integrated circuit may be formed by forming a sacrificial silicon nitride feature. At least a portion of the sacrificial silicon nitride feature may be removed by placing the integrated circuit in a two-step oxidized layer etch tool and removing a surface layer of oxidized silicon from the sacrificial silicon nitride feature using a two-step etch process. The two-step etch process exposes the integrated circuits to reactants from a plasma source at a temperature less than 40° C. and subsequently heating the integrated circuit to 80° C. to 120° C. while in the two-step oxidized layer etch tool. While the integrated circuit is in the two-step oxidized layer etch tool, without exposing the integrated circuit to an ambient containing more than 1 torr of oxygen, at least a portion of the sacrificial silicon nitride feature is removed using fluorine-containing etch reagents, substantially free of ammonia.
    Type: Application
    Filed: August 4, 2016
    Publication date: November 24, 2016
    Inventors: Tom Lii, David Farber
  • Publication number: 20160307808
    Abstract: An integrated circuit may be formed by removing source/drain spacers from offset spacers on sidewalls of MOS transistor gates, forming a contact etch stop layer (CESL) spacer layer on lateral surfaces of the MOS transistor gates, etching back the CESL spacer layer to form sloped CESL spacers on the lateral surfaces of the MOS transistor gates with heights of ¼ to ¾ of the MOS transistor gates, forming a CESL over the sloped CESL spacers, the MOS transistor gates and the intervening substrate, and forming a PMD layer over the CESL.
    Type: Application
    Filed: June 27, 2016
    Publication date: October 20, 2016
    Inventor: Tom Lii
  • Patent number: 9437449
    Abstract: An integrated circuit may be formed by forming a sacrificial silicon nitride feature. At least a portion of the sacrificial silicon nitride feature may be removed by placing the integrated circuit in a two-step oxidized layer etch tool and removing a surface layer of oxidized silicon from the sacrificial silicon nitride feature using a two-step etch process. The two-step etch process exposes the integrated circuits to reactants from a plasma source at a temperature less than 40° C. and subsequently heating the integrated circuit to 80° C. to 120° C. while in the two-step oxidized layer etch tool. While the integrated circuit is in the two-step oxidized layer etch tool, without exposing the integrated circuit to an ambient containing more than 1 torr of oxygen, at least a portion of the sacrificial silicon nitride feature is removed using fluorine-containing etch reagents, substantially free of ammonia.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: September 6, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Tom Lii, David Farber
  • Patent number: 9406779
    Abstract: An integrated circuit may be formed by removing source/drain spacers from offset spacers on sidewalls of MOS transistor gates, forming a contact etch stop layer (CESL) spacer layer on lateral surfaces of the MOS transistor gates, etching back the CESL spacer layer to form sloped CESL spacers on the lateral surfaces of the MOS transistor gates with heights of ¼ to ¾ of the MOS transistor gates, forming a CESL over the sloped CESL spacers, the MOS transistor gates and the intervening substrate, and forming a PMD layer over the CESL.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: August 2, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Patent number: 9385044
    Abstract: An integrated circuit containing metal replacement gates may be formed by forming a CMP stop layer over sacrificial gates, and forming a dielectric fill layer over the CMP stop layer. Dielectric material from the dielectric fill layer is removed from over the sacrificial gates using a CMP process which exposes the CMP stop layer over the sacrificial gates but does not expose the sacrificial gates. The CMP stop layer is removed from over the sacrificial gates using a plasma etch process. In one version, the plasma etch process may be selective to the CMP stop layer. In another version, the plasma etch process may be a non-selective etch process. After the sacrificial gates are exposed by the plasma etch process, the sacrificial gates are removed and the metal replacement gates are formed.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: July 5, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Patent number: 9224657
    Abstract: An integrated circuit is formed to include a first polarity MOS transistor and a second, opposite, polarity MOS transistor. A hard mask of silicon-doped boron nitride (SixBN) with 1 atomic percent to 30 atomic percent silicon is formed over the first polarity MOS transistor and the second polarity MOS transistor. The hard mask is removed from source/drain regions of the first polarity MOS transistor and left in place over the second polarity MOS transistor. Semiconductor material is epitaxially grown at the source/drain regions of the first polarity MOS transistor while the hard mask is in place. Subsequently, the hard mask is removed from the second polarity MOS transistor.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: December 29, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: David Gerald Farber, Tom Lii, Brian K. Kirkpatrick
  • Publication number: 20150287804
    Abstract: An integrated circuit may be formed by removing source/drain spacers from offset spacers on sidewalls of MOS transistor gates, forming a contact etch stop layer (CESL) spacer layer on lateral surfaces of the MOS transistor gates, etching back the CESL spacer layer to form sloped CESL spacers on the lateral surfaces of the MOS transistor gates with heights of ¼ to ¾ of the MOS transistor gates, forming a CESL over the sloped CESL spacers, the MOS transistor gates and the intervening substrate, and forming a PMD layer over the CESL.
    Type: Application
    Filed: June 22, 2015
    Publication date: October 8, 2015
    Inventor: Tom Lii
  • Publication number: 20150287723
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PMD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Application
    Filed: June 22, 2015
    Publication date: October 8, 2015
    Inventor: Tom Lii
  • Patent number: 9093380
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PAD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Grant
    Filed: June 5, 2013
    Date of Patent: July 28, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Tom Lii
  • Patent number: 9093303
    Abstract: An integrated circuit may be formed by removing source/drain spacers from offset spacers on sidewalls of MOS transistor gates, forming a contact etch stop layer (CESL) spacer layer on lateral surfaces of the MOS transistor gates, etching back the CESL spacer layer to form sloped CESL spacers on the lateral surfaces of the MOS transistor gates with heights of ¼ to ¾ of the MOS transistor gates, forming a CESL over the sloped CESL spacers, the MOS transistor gates and the intervening substrate, and forming a PMD layer over the CESL.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: July 28, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORTED
    Inventor: Tom Lii
  • Publication number: 20150187661
    Abstract: A process for forming an integrated circuit with an embedded epitaxially grown semiconductor using an epi blocking bilayer. The epi blocking bilayer comprised of a two different materials that may be etched selectively with respect to each other such as silicon nitride and silicon dioxide.
    Type: Application
    Filed: December 18, 2014
    Publication date: July 2, 2015
    Inventors: Tom Lii, David Farber
  • Patent number: 9054158
    Abstract: The width of a metal contact opening is formed to be smaller than the minimum feature size of a photolithographically-defined opening. The method forms the metal contact opening by first etching the fourth layer of a multilayered hard mask structure to have a number of trenches that expose the third layer of the multilayered hard mask structure. Following this, the third, second, and first layers of the multilayered hard mask structure are selectively etched to expose uncovered regions on the top surface of an isolation layer that touches and lies over a source region and a drain region. The uncovered regions on the top surface of the isolation layer are then etched to form the metal contact openings.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: June 9, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: David Gerald Farber, Tom Lii, Steve Lytle
  • Publication number: 20150044830
    Abstract: An integrated circuit is formed to include a first polarity MOS transistor and a second, opposite, polarity MOS transistor. A hard mask of silicon-doped boron nitride (SixBN) with 1 atomic percent to 30 atomic percent silicon is formed over the first polarity MOS transistor and the second polarity MOS transistor. The hard mask is removed from source/drain regions of the first polarity MOS transistor and left in place over the second polarity MOS transistor. Semiconductor material is epitaxially grown at the source/drain regions of the first polarity MOS transistor while the hard mask is in place. Subsequently, the hard mask is removed from the second polarity MOS transistor.
    Type: Application
    Filed: August 6, 2013
    Publication date: February 12, 2015
    Applicant: Texas Instruments Incorporated
    Inventors: David Gerald Farber, Tom Lii, Brian K. Kirkpatrick
  • Publication number: 20140361376
    Abstract: A method for forming MOS transistor includes providing a substrate including a semiconductor surface having a gate electrode on a gate dielectric thereon, dielectric spacers on sidewalls of the gate electrode, a source and drain in the semiconductor surface on opposing sides of the gate electrode, and a pre-metal dielectric (PMD) layer over the gate electrode and over the source and drain regions. Contact holes are formed through the PMD layer to form a contact to the gate electrode and contacts to the source and drain. A post contact etch dielectric layer is then deposited on the contacts to source and drain and on sidewalls of the PMD layer. The post contact etch dielectric layer is selectively removed from the contacts to leave a dielectric liner on sidewalls of the PMD layer. A metal silicide layer is formed on the contacts to the source and drain.
    Type: Application
    Filed: June 5, 2013
    Publication date: December 11, 2014
    Inventor: TOM LII
  • Publication number: 20140227877
    Abstract: The width of a metal contact opening is formed to be smaller than the minimum feature size of a photolithographically-defined opening. The method forms the metal contact opening by first etching the fourth layer of a multilayered hard mask structure to have a number of trenches that expose the third layer of the multilayered hard mask structure. Following this, the third, second, and first layers of the multilayered hard mask structure are selectively etched to expose uncovered regions on the top surface of an isolation layer that touches and lies over a source region and a drain region. The uncovered regions on the top surface of the isolation layer are then etched to form the metal contact openings.
    Type: Application
    Filed: February 8, 2013
    Publication date: August 14, 2014
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: David Gerald Farber, Tom Lii, Steve Lytle