Patents by Inventor Veeraraghavan Basker

Veeraraghavan Basker 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: 11887890
    Abstract: Partial self-aligned contact structures are provided. In one aspect, a method of forming a semiconductor device includes: patterning fins in a substrate; forming a gate(s) over the fins, separated from source/drains by first spacers, wherein a lower portion of the gate(s) includes a workfunction-setting metal, and an upper portion of the gate(s) includes a core metal between a metal liner; recessing the metal liner to form divots in the upper portion of the gate(s) in between the first spacers and the core metal; forming second spacers in the divots such that the first spacers and the second spacers surround the core metal in the upper portion of the gate(s); forming lower source/drain contacts in between the first spacers over the source/drains; recessing the lower source/drain contacts to form gaps over the lower source/drain contacts; and forming source/drain caps in the gaps. A semiconductor device is also provided.
    Type: Grant
    Filed: December 17, 2021
    Date of Patent: January 30, 2024
    Assignee: International Business Machines Corporation
    Inventors: Ruilong Xie, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Patent number: 11862710
    Abstract: A semiconductor device includes a first source/drain region on an upper surface of a semiconductor substrate that extends along a first direction to define a length and a second direction opposite the first direction to define a width. A channel region extends vertically in a direction perpendicular to the first and second directions from a first end contacting the first source/drain region to an opposing second end contacting a second source/drain region. A gate surrounds a channel portion of the channel region, and a first doped source/drain extension region is located between the first source/drain region and the channel portion. The first doped source/drain extension region has a thickness extending along the vertical direction. A second doped source/drain extension region is located between the second source/drain region and the channel portion. The second doped source/drain extension region has a thickness extending along the vertical direction that matches the first thickness.
    Type: Grant
    Filed: January 6, 2022
    Date of Patent: January 2, 2024
    Assignee: International Business Machines Corporation
    Inventors: Chun-Chen Yeh, Alexander Reznicek, Veeraraghavan Basker, Junli Wang
  • Patent number: 11349001
    Abstract: A method of fabricating a static random-access memory (SRAM) device includes forming a sacrificial material and replacing the sacrificial material with a metal to form a cross-couple contact on a metal gate stack. A portion of the metal gate stack directly contacts each of a sidewall and an endwall of the cross-couple contact.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: May 31, 2022
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ruilong Xie, Carl Radens, Kangguo Cheng, Veeraraghavan Basker, Juntao Li
  • Publication number: 20220130980
    Abstract: A semiconductor device includes a first source/drain region on an upper surface of a semiconductor substrate that extends along a first direction to define a length and a second direction opposite the first direction to define a width. A channel region extends vertically in a direction perpendicular to the first and second directions from a first end contacting the first source/drain region to an opposing second end contacting a second source/drain region. A gate surrounds a channel portion of the channel region, and a first doped source/drain extension region is located between the first source/drain region and the channel portion. The first doped source/drain extension region has a thickness extending along the vertical direction. A second doped source/drain extension region is located between the second source/drain region and the channel portion. The second doped source/drain extension region has a thickness extending along the vertical direction that matches the first thickness.
    Type: Application
    Filed: January 6, 2022
    Publication date: April 28, 2022
    Inventors: Chun-Chen Yeh, Alexander Reznicek, Veeraraghavan Basker, Junli Wang
  • Publication number: 20220108923
    Abstract: Partial self-aligned contact structures are provided. In one aspect, a method of forming a semiconductor device includes: patterning fins in a substrate; forming a gate(s) over the fins, separated from source/drains by first spacers, wherein a lower portion of the gate(s) includes a workfunction-setting metal, and an upper portion of the gate(s) includes a core metal between a metal liner; recessing the metal liner to form divots in the upper portion of the gate(s) in between the first spacers and the core metal; forming second spacers in the divots such that the first spacers and the second spacers surround the core metal in the upper portion of the gate(s); forming lower source/drain contacts in between the first spacers over the source/drains; recessing the lower source/drain contacts to form gaps over the lower source/drain contacts; and forming source/drain caps in the gaps. A semiconductor device is also provided.
    Type: Application
    Filed: December 17, 2021
    Publication date: April 7, 2022
    Inventors: Ruilong Xie, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Patent number: 11239343
    Abstract: A semiconductor device includes a first source/drain region on an upper surface of a semiconductor substrate that extends along a first direction to define a length and a second direction opposite the first direction to define a width. A channel region extends vertically in a direction perpendicular to the first and second directions from a first end contacting the first source/drain region to an opposing second end contacting a second source/drain region. A gate surrounds a channel portion of the channel region, and a first doped source/drain extension region is located between the first source/drain region and the channel portion. The first doped source/drain extension region has a thickness extending along the vertical direction. A second doped source/drain extension region is located between the second source/drain region and the channel portion. The second doped source/drain extension region has a thickness extending along the vertical direction that matches the first thickness.
    Type: Grant
    Filed: February 21, 2020
    Date of Patent: February 1, 2022
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chun-Chen Yeh, Alexander Reznicek, Veeraraghavan Basker, Junli Wang
  • Patent number: 11239115
    Abstract: Partial self-aligned contact structures are provided. In one aspect, a method of forming a semiconductor device includes: patterning fins in a substrate; forming a gate(s) over the fins, separated from source/drains by first spacers, wherein a lower portion of the gate(s) includes a workfunction-setting metal, and an upper portion of the gate(s) includes a core metal between a metal liner; recessing the metal liner to form divots in the upper portion of the gate(s) in between the first spacers and the core metal; forming second spacers in the divots such that the first spacers and the second spacers surround the core metal in the upper portion of the gate(s); forming lower source/drain contacts in between the first spacers over the source/drains; recessing the lower source/drain contacts to form gaps over the lower source/drain contacts; and forming source/drain caps in the gaps. A semiconductor device is also provided.
    Type: Grant
    Filed: October 30, 2019
    Date of Patent: February 1, 2022
    Assignee: International Business Machines Corporation
    Inventors: Ruilong Xie, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Patent number: 11183558
    Abstract: Embodiments of the invention are directed to a method of performing fabrication operations to form a nanosheet field effect transistor (FET) device. The fabrication operations include forming a nanosheet stack over a portion of a substrate. A first source or drain (S/D) trench is formed adjacent to a first end of the nanosheet stack. A second S/D trench is formed adjacent to a second end of the nanosheet stack. A region of the substrate is removed to form a bottom dielectric isolation (BDI) cavity in the substrate, wherein the BDI cavity is positioned beneath at least the nanosheet stack, the first S/D trench, and the second S/D trench. The BDI cavity is filled with a dielectric material, thereby forming a BDI region positioned beneath at least the nanosheet stack, the first S/D trench, and the second S/D trench.
    Type: Grant
    Filed: February 10, 2020
    Date of Patent: November 23, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chun-Chen Yeh, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Publication number: 20210265488
    Abstract: A semiconductor device includes a first source/drain region on an upper surface of a semiconductor substrate that extends along a first direction to define a length and a second direction opposite the first direction to define a width. A channel region extends vertically in a direction perpendicular to the first and second directions from a first end contacting the first source/drain region to an opposing second end contacting a second source/drain region. A gate surrounds a channel portion of the channel region, and a first doped source/drain extension region is located between the first source/drain region and the channel portion. The first doped source/drain extension region has a thickness extending along the vertical direction. A second doped source/drain extension region is located between the second source/drain region and the channel portion. The second doped source/drain extension region has a thickness extending along the vertical direction that matches the first thickness.
    Type: Application
    Filed: February 21, 2020
    Publication date: August 26, 2021
    Inventors: Chun-Chen Yeh, Alexander Reznicek, Veeraraghavan Basker, Junli Wang
  • Publication number: 20210249506
    Abstract: Embodiments of the invention are directed to a method of performing fabrication operations to form a nanosheet field effect transistor (FET) device. The fabrication operations include forming a nanosheet stack over a portion of a substrate. A first source or drain (S/D) trench is formed adjacent to a first end of the nanosheet stack. A second S/D trench is formed adjacent to a second end of the nanosheet stack. A region of the substrate is removed to form a bottom dielectric isolation (BDI) cavity in the substrate, wherein the BDI cavity is positioned beneath at least the nanosheet stack, the first S/D trench, and the second S/D trench. The BDI cavity is filled with a dielectric material, thereby forming a BDI region positioned beneath at least the nanosheet stack, the first S/D trench, and the second S/D trench.
    Type: Application
    Filed: February 10, 2020
    Publication date: August 12, 2021
    Inventors: Chun-Chen Yeh, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Patent number: 11024536
    Abstract: Embodiments of the present invention are directed to reducing the effective capacitance between active devices at the contact level. In a non-limiting embodiment of the invention, an interlayer dielectric is replaced with a low-k material without damaging a self-aligned contact (SAC) cap. A gate can be formed over a channel region of a fin. The gate can include a gate spacer and a SAC cap. Source and drain regions can be formed adjacent to the channel region. A contact is formed on the SAC cap and on surfaces of the source and drain regions. A first dielectric layer can be recessed to expose a sidewall of the contact and a sidewall of the gate spacer. A second dielectric layer can be formed on the recessed surface of the first dielectric layer. The second dielectric layer can include a dielectric material having a dielectric constant less than the first dielectric layer.
    Type: Grant
    Filed: April 18, 2019
    Date of Patent: June 1, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Adra Carr, Vimal Kamineni, Ruilong Xie, Andrew Greene, Nigel Cave, Veeraraghavan Basker
  • Publication number: 20210134671
    Abstract: Partial self-aligned contact structures are provided. In one aspect, a method of forming a semiconductor device includes: patterning fins in a substrate; forming a gate(s) over the fins, separated from source/drains by first spacers, wherein a lower portion of the gate(s) includes a workfunction-setting metal, and an upper portion of the gate(s) includes a core metal between a metal liner; recessing the metal liner to form divots in the upper portion of the gate(s) in between the first spacers and the core metal; forming second spacers in the divots such that the first spacers and the second spacers surround the core metal in the upper portion of the gate(s); forming lower source/drain contacts in between the first spacers over the source/drains; recessing the lower source/drain contacts to form gaps over the lower source/drain contacts; and forming source/drain caps in the gaps. A semiconductor device is also provided.
    Type: Application
    Filed: October 30, 2019
    Publication date: May 6, 2021
    Inventors: Ruilong Xie, Veeraraghavan Basker, Alexander Reznicek, Junli Wang
  • Patent number: 10998234
    Abstract: Embodiments of the present invention are directed to a method that prevents punch-through of a bottom isolation layer and improves the quality of the source/drain epitaxial growth in a nanosheet semiconductor structure. In a non-limiting embodiment of the invention, a bottom isolation structure is formed over a substrate. The bottom isolation structure includes a tri-layer stack in a first region of the substrate and a bi-layer stack in a second region of the substrate. A nanosheet stack is formed over the bottom isolation structure in the first region of the substrate. A gate is formed over a channel region of the nanosheet stack.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: May 4, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ruilong Xie, Veeraraghavan Basker, Nicolas Loubet, Balasubramanian Pranatharthiharan
  • Publication number: 20210111028
    Abstract: A method of fabricating a static random-access memory (SRAM) device includes forming a sacrificial material and replacing the sacrificial material with a metal to form a cross-couple contact on a metal gate stack. A portion of the metal gate stack directly contacts each of a sidewall and an endwall of the cross-couple contact.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 15, 2021
    Inventors: Ruilong Xie, Carl Radens, Kangguo Cheng, Veeraraghavan Basker, Juntao LI
  • Patent number: 10943990
    Abstract: Gate contact over active layout designs are provided. In one aspect, a method for forming a gate contact over active device includes: forming a device including metal gates over an active area of a wafer, and source/drains on opposite sides of the metal gates offset by gate spacers; recessing the metal gates/gate spacers; forming etch-selective spacers on top of the recessed gate spacers; forming gate caps on top of the recessed metal gates; forming source/drain contacts on the source/drains; forming source/drain caps on top of the source/drain contacts, wherein the etch-selective spacers provide etch selectivity to the gate caps and source/drain caps; and forming a metal gate contact that extends through one of the gate caps, wherein the etch-selective spacers prevent gate-to-source drain shorting by the metal gate contact. Alternate etch-selective configurations are also provided including a claw-shaped source/drain cap design. A gate contact over active device is also provided.
    Type: Grant
    Filed: October 25, 2018
    Date of Patent: March 9, 2021
    Assignee: International Business Machines Corporation
    Inventors: Andrew Greene, Victor W. C. Chan, Gangadhara Raja Muthinti, Veeraraghavan Basker, Junli Wang, Kisik Choi, Su Chen Fan
  • Patent number: 10872809
    Abstract: One illustrative transistor device disclosed herein includes a gate structure positioned above at least an active region, wherein the gate structure has an axial length in a direction corresponding to a gate width direction of the transistor device. In this example, a first portion of the axial length of the gate structure has a first upper surface and a second portion of the axial length of the gate structure has a second upper surface, wherein the first upper surface is positioned at a level that is above a level of the second upper surface. The device also includes a gate contact structure that contacts the first upper surface of the gate structure.
    Type: Grant
    Filed: September 23, 2019
    Date of Patent: December 22, 2020
    Assignee: GLOBALFOUNDRIES Inc.
    Inventors: Ruilong Xie, Lars W. Liebmann, Balasubramanian Pranatharthi Haran, Veeraraghavan Basker
  • Publication number: 20200365687
    Abstract: Embodiments of the present invention are directed to a method that prevents punch-through of a bottom isolation layer and improves the quality of the source/drain epitaxial growth in a nanosheet semiconductor structure. In a non-limiting embodiment of the invention, a bottom isolation structure is formed over a substrate. The bottom isolation structure includes a tri-layer stack in a first region of the substrate and a bi-layer stack in a second region of the substrate. A nanosheet stack is formed over the bottom isolation structure in the first region of the substrate. A gate is formed over a channel region of the nanosheet stack.
    Type: Application
    Filed: May 14, 2019
    Publication date: November 19, 2020
    Inventors: Ruilong Xie, Veeraraghavan Basker, Nicolas Loubet, Balasubramanian Pranatharthiharan
  • Publication number: 20200335392
    Abstract: Embodiments of the present invention are directed to reducing the effective capacitance between active devices at the contact level. In a non-limiting embodiment of the invention, an interlayer dielectric is replaced with a low-k material without damaging a self-aligned contact (SAC) cap. A gate can be formed over a channel region of a fin. The gate can include a gate spacer and a SAC cap. Source and drain regions can be formed adjacent to the channel region. A contact is formed on the SAC cap and on surfaces of the source and drain regions. A first dielectric layer can be recessed to expose a sidewall of the contact and a sidewall of the gate spacer. A second dielectric layer can be formed on the recessed surface of the first dielectric layer. The second dielectric layer can include a dielectric material having a dielectric constant less than the first dielectric layer.
    Type: Application
    Filed: April 18, 2019
    Publication date: October 22, 2020
    Inventors: Adra Carr, Vimal Kamineni, Ruilong Xie, Andrew Greene, Nigel Cave, Veeraraghavan Basker
  • Publication number: 20200135886
    Abstract: Gate contact over active layout designs are provided. In one aspect, a method for forming a gate contact over active device includes: forming a device including metal gates over an active area of a wafer, and source/drains on opposite sides of the metal gates offset by gate spacers; recessing the metal gates/gate spacers; forming etch-selective spacers on top of the recessed gate spacers; forming gate caps on top of the recessed metal gates; forming source/drain contacts on the source/drains; forming source/drain caps on top of the source/drain contacts, wherein the etch-selective spacers provide etch selectivity to the gate caps and source/drain caps; and forming a metal gate contact that extends through one of the gate caps, wherein the etch-selective spacers prevent gate-to-source drain shorting by the metal gate contact. Alternate etch-selective configurations are also provided including a claw-shaped source/drain cap design. A gate contact over active device is also provided.
    Type: Application
    Filed: October 25, 2018
    Publication date: April 30, 2020
    Inventors: Andrew Greene, Victor W.C. Chan, Gangadhara Raja Muthinti, Veeraraghavan Basker, Junli Wang, Kisik Choi, Su Chen Fan
  • Patent number: 10586739
    Abstract: A technique relates to forming a self-aligning field effect transistor. A starting punch through stopper comprising a substrate having a plurality of fins patterned thereon, an n-type field effect transistor (NFET) region, a p-type field effect transistor (PFET) region, and a center region having a boundary defect at the interface of the NFET region and the PFET region is first provided. The field effect transistor is then masked to mask the NFET region and the PFET region such that the center region is exposed. A center boundary region is then formed by etching the center region to remove the boundary defect.
    Type: Grant
    Filed: October 27, 2017
    Date of Patent: March 10, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Veeraraghavan Basker, Kangguo Cheng, Theodorus Standaert, Junli Wang