Patents by Inventor Hemanth Jagannathan

Hemanth Jagannathan 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: 11152265
    Abstract: A vertical field effect transistor structure and method for fabricating the same. The structure includes a source/drain layer in contact with at least one semiconductor fin. An edge portion of the source/drain layer includes a notched region filled with a dielectric material. A spacer layer includes a first portion in contact with the source/drain layer and a second portion in contact with the dielectric material. A gate structure contacts the spacer layer and the dielectric material. The method includes forming a source/drain layer in contact with at least one semiconductor fin. A spacer layer is formed in contact with the source/drain layer. A portion of the spacer layer is removed to expose an end portion of the source/drain layer. The exposed end portion of the source/drain layer is recessed to form a notched region within the source/drain layer. A dielectric layer is formed within the notched region.
    Type: Grant
    Filed: August 1, 2019
    Date of Patent: October 19, 2021
    Assignee: International Business Machines Corporation
    Inventors: Ruilong Xie, Hemanth Jagannathan, Christopher J. Waskiewicz, Alexander Reznicek
  • Publication number: 20210320186
    Abstract: Semiconductor devices and methods of forming the same include forming a bottom source/drain structure around a fin. A multi-layer bottom spacer is formed on the bottom source/drain structure, around the fin. Each layer of the multi-layer bottom spacer has a respective vertical height above the bottom source/drain structure, with a layer of the multi-layer bottom spacer that is farthest from the fin having a greater vertical height than a layer that is closest to the fin, to address parasitic capacitance from the bottom source/drain structure.
    Type: Application
    Filed: April 14, 2020
    Publication date: October 14, 2021
    Inventors: Ruilong Xie, Hemanth Jagannathan, Jay William Strane, Eric Miller
  • Patent number: 11145555
    Abstract: A method of forming a semiconductor structure includes forming a plurality of fins over a top surface of a substrate, and forming one or more vertical transport field-effect transistors from the plurality of fins, the plurality of fins providing channels for the one or more vertical transport field-effect transistors. The method also includes forming a gate stack for the one or more vertical transport field-effect transistors surrounding at least a portion of the plurality of fins, the gate stack including a gate dielectric formed over the plurality of fins, a work function metal layer formed over the gate dielectric, and a gate conductor formed over the work function metal layer. The gate stack comprises a box profile in an area between at least two adjacent ones of the plurality of fins.
    Type: Grant
    Filed: March 20, 2020
    Date of Patent: October 12, 2021
    Assignee: International Business Machines Corporation
    Inventors: Shogo Mochizuki, ChoongHyun Lee, Hemanth Jagannathan
  • Publication number: 20210305104
    Abstract: A method includes forming a p-type field effect transistor region and an n-type field effect transistor region into a semiconductor substrate. The method implements a process flow to fabricate highly doped top source/drains with minimal lithography and etching processes. The method permits the formation of VFETs with increased functionality and reduced scaling.
    Type: Application
    Filed: March 24, 2020
    Publication date: September 30, 2021
    Inventors: Heng Wu, Ruilong Xie, Su Chen Fan, Jay William Strane, Hemanth Jagannathan
  • Patent number: 11121209
    Abstract: A method for forming a metal-insulator-metal (MIM) capacitor on a semiconductor substrate is presented. The method includes forming a first electrode defining columnar grains, forming a dielectric layer over the first electrode, and forming a second electrode over the dielectric layer. The first and second electrodes can be titanium nitride (TiN) electrodes. The dielectric layer can include one of hafnium oxide and zirconium oxide deposited by atomic layer deposition (ALD). The ALD results in deposition of high-k films in grain boundaries of the first electrode.
    Type: Grant
    Filed: March 27, 2017
    Date of Patent: September 14, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Takashi Ando, Eduard A. Cartier, Hemanth Jagannathan, Paul C. Jamison, Vijay Narayanan
  • Patent number: 11094801
    Abstract: According to an embodiment of the present invention, a semiconductor structure includes a semiconductor substrate and a plurality of fins located on the semiconductor substrate. The plurality of fins each independently includes a bottom fin portion, a top fin portion layer, and an isolated oxide layer located in between the bottom fin portion and the top fin portion layer in the y-direction parallel to the height of the plurality of fins. The isolated oxide layer includes a mixed oxide region located in between oxidized regions in an x-direction perpendicular to the height of the plurality of fins.
    Type: Grant
    Filed: April 9, 2020
    Date of Patent: August 17, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ruqiang Bao, Hemanth Jagannathan, Paul C. Jamison, Choonghyun Lee
  • Patent number: 11088033
    Abstract: A semiconductor structure and a method for fabricating the same. The semiconductor structure includes at least one semiconductor fin disposed on a substrate. A disposable gate contacts the at least one semiconductor fin. A spacer is disposed on the at least one semiconductor fin and in contact with the disposable gate. Epitaxially grown source and drain regions are disposed at least partially within the at least one semiconductor fin. A first one of silicide and germanide is disposed on and in contact with the source region. A second one of one of silicide and germanide is disposed on and in contact with the drain region. The method includes epitaxially growing source/drain regions within a semiconductor fin. A contact metal layer contacts the source/drain regions. One of a silicide and a germanide is formed on the source/drain regions from the contact metal layer prior to removing the disposable gate.
    Type: Grant
    Filed: September 8, 2016
    Date of Patent: August 10, 2021
    Assignee: International Business Machines Corporation
    Inventors: Praneet Adusumilli, Hemanth Jagannathan, Christian Lavoie, Ahmet S. Ozcan
  • Publication number: 20210217889
    Abstract: A semiconductor device includes a substrate, at least one semiconductor vertical fin extending from the substrate, a bottom source/drain region disposed beneath the at least one semiconductor vertical fin, and first and second isolation regions on respective longitudinal sides of the semiconductor vertical fin. Each of the first and second isolation regions extend vertically above the bottom source/drain region. A bottom spacer is disposed on the first and second isolation regions. A spacer segment of the bottom spacer is disposed on a first upper surface portion of the bottom source/drain region adjacent the first isolation region. A dielectric liner underlies at least portions of the first and second isolation regions. A dielectric segment of the dielectric liner is disposed on a second upper surface portion of the bottom source/drain region adjacent the second isolation region. At least one functional gate structure is disposed on the semiconductor vertical fin.
    Type: Application
    Filed: January 9, 2020
    Publication date: July 15, 2021
    Inventors: Christopher J. Waskiewicz, Ruilong Xie, Jay William Strane, Hemanth Jagannathan
  • Patent number: 11062956
    Abstract: A semiconductor structure and a method for fabricating the same. The semiconductor structure includes at least one semiconductor fin disposed on a substrate. A disposable gate contacts the at least one semiconductor fin. A spacer is disposed on the at least one semiconductor fin and in contact with the disposable gate. Epitaxially grown source and drain regions are disposed at least partially within the at least one semiconductor fin. A first one of silicide and germanide is disposed on and in contact with the source region. A second one of one of silicide and germanide is disposed on and in contact with the drain region. The method includes epitaxially growing source/drain regions within a semiconductor fin. A contact metal layer contacts the source/drain regions. One of a silicide and a germanide is formed on the source/drain regions from the contact metal layer prior to removing the disposable gate.
    Type: Grant
    Filed: December 27, 2017
    Date of Patent: July 13, 2021
    Assignee: International Business Machines Corporation
    Inventors: Praneet Adusumilli, Hemanth Jagannathan, Christian Lavoie, Ahmet S. Ozcan
  • Publication number: 20210151583
    Abstract: A semiconductor device structure and a method for fabricating the semiconductor device structure are disclosed. The method includes receiving a substrate stack including at least one semiconductor fin, the substrate stack including: a bottom source/drain epi region directly below the semiconductor fin; a vertical gate structure directly above the bottom source/drain epi region and in contact with the semiconductor fin; a first inter-layer dielectric in contact with a sidewall of the vertical gate structure; and a second interlayer-layer dielectric directly above and contacting a top surface of the first inter-layer dielectric. The method further including: etching a top region of the semiconductor fin and the gate structure thereby creating a recess directly above the top region of the semiconductor fin and the vertical gate structure; and forming in the recess a top source/drain epi region directly above, and contacting, a top surface of the semiconductor fin.
    Type: Application
    Filed: December 28, 2020
    Publication date: May 20, 2021
    Inventors: Wenyu XU, Ruilong Xie, Pietro MONTANINI, Hemanth JAGANNATHAN
  • Publication number: 20210111246
    Abstract: A nonplanar MOSFET device such as a FinFET or a sacked nanosheets/nanowires FET has a substrate, one or more nonplanar channels disposed on the substrate, and a gate stack enclosing the nonplanar channels. A first source/drain (S/D) region is disposed on the substrate on a source side of the nonplanar channel and second S/D region is disposed on the substrate on a drain side of the nonplanar channel. The first and second S/D regions made of silicon-germanium (SiGe). In some embodiments, both S/D regions are p-type doped. Contact trenches provide a metallic electrical connection to the first and the second source/drain (S/D) regions. The S/D regions have two parts, a first part with a first concentration of germanium (Ge) and a second part with a second, higher Ge concentration that is a surface layer having convex shape and aligned with one of the contact trenches.
    Type: Application
    Filed: October 14, 2019
    Publication date: April 15, 2021
    Inventors: Fee Li Lie, Choonghyun Lee, Kangguo Cheng, Hemanth Jagannathan, Oleg Gluschenkov
  • Patent number: 10978551
    Abstract: A method for forming a metal-insulator-metal (MIM) capacitor on a semiconductor substrate is presented. The method includes forming a first electrode defining columnar grains, forming a dielectric layer over the first electrode, and forming a second electrode over the dielectric layer. The first and second electrodes can be titanium nitride (TiN) electrodes. The dielectric layer can include one of hafnium oxide and zirconium oxide deposited by atomic layer deposition (ALD). The ALD results in deposition of high-k films in grain boundaries of the first electrode.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: April 13, 2021
    Assignee: International Business Machines Corporation
    Inventors: Takashi Ando, Eduard A. Cartier, Hemanth Jagannathan, Paul C. Jamison, Vijay Narayanan
  • Patent number: 10978550
    Abstract: A capacitor includes a stack. The stack has a first metallic layer formed over a substrate, an insulator formed over the first metallic layer, and a second metallic layer formed over the insulator. The first metallic layer has at least one high domain and at least one low domain, where a surface of the substrate in the at least one low domain has a height that is lower than a surface of the substrate in the at least one high domain.
    Type: Grant
    Filed: May 11, 2020
    Date of Patent: April 13, 2021
    Assignee: Tessera, Inc.
    Inventors: Kisup Chung, Isabel C. Estrada-Raygoza, Hemanth Jagannathan, Chi-Chun Liu, Yann A. M. Mignot, Hao Tang
  • Patent number: 10971626
    Abstract: Techniques for interface charge reduction to improve performance of SiGe channel devices are provided. In one aspect, a method for reducing interface charge density (Dit) for a SiGe channel material includes: contacting the SiGe channel material with an Si-containing chemical precursor under conditions sufficient to form a thin continuous Si layer, e.g., less than 5 monolayers thick on a surface of the SiGe channel material which is optionally contacted with an n-dopant precursor; and depositing a gate dielectric on the SiGe channel material over the thin continuous Si layer, wherein the thin continuous Si layer by itself or in conjunction with n-dopant precursor passivates an interface between the SiGe channel material and the gate dielectric thereby reducing the Dit. A FET device and method for formation thereof are also provided.
    Type: Grant
    Filed: July 3, 2019
    Date of Patent: April 6, 2021
    Assignee: International Business Machines Corporation
    Inventors: Devendra Sadana, Dechao Guo, Joel P. de Souza, Ruqiang Bao, Stephen W. Bedell, Shogo Mochizuki, Gen Tsutsui, Hemanth Jagannathan, Marinus Hopstaken
  • Publication number: 20210098597
    Abstract: A method of forming a vertical channel semiconductor structure, comprises forming a source/drain layer in contact with at least one semiconductor fin. A first sacrificial layer is formed over the source/drain layer. A second sacrificial layer is formed over the first sacrificial layer. A trench is formed in the second sacrificial layer to expose a portion of the first sacrificial layer. After forming the second sacrificial layer, the first sacrificial layer is selectively removed to form a cavity under the second sacrificial layer. A spacer layer is then formed within the cavity.
    Type: Application
    Filed: September 27, 2019
    Publication date: April 1, 2021
    Inventors: Ruilong Xie, Heng WU, Jay STRANE, Hemanth JAGANNATHAN, Lan YU, Tao LI
  • Patent number: 10937890
    Abstract: A method for forming a semiconductor device is disclosed. The method includes receiving a substrate stack including at least one semiconductor fin, the substrate stack including: a bottom source/drain epi region directly below the semiconductor fin; a vertical gate structure directly above the bottom source/drain epi region and in contact with the semiconductor fin; a first inter-layer dielectric in contact with a sidewall of the vertical gate structure; and a second interlayer-layer dielectric directly above and contacting a top surface of the first inter-layer dielectric. The method further including: etching a top region of the semiconductor fin and the gate structure thereby creating a recess directly above the top region of the semiconductor fin and the vertical gate structure; and forming in the recess a top source/drain epi region directly above, and contacting, a top surface of the semiconductor fin. A novel semiconductor device structure is also disclosed.
    Type: Grant
    Filed: April 3, 2019
    Date of Patent: March 2, 2021
    Assignee: International Business Machines Corporation
    Inventors: Wenyu Xu, Ruilong Xie, Pietro Montanini, Hemanth Jagannathan
  • Patent number: 10930566
    Abstract: An electrical device that includes a p-type semiconductor device having a p-type work function gate structure including a first high-k gate dielectric, a first metal containing buffer layer, a first titanium nitride layer having a first thickness present on the metal containing buffer layer, and a first gate conductor contact. A mid gap semiconductor device having a mid gap gate structure including a second high-k gate dielectric, a second metal containing buffer layer, a second titanium nitride layer having a second thickness that is less than the first thickness present, and a second gate conductor contact. An n-type semiconductor device having an n-type work function gate structure including a third high-k gate dielectric present on a channel region of the n-type semiconductor device, a third metal containing buffer layer on the third high-k gate dielectric and a third gate conductor fill present atop the third metal containing buffer layer.
    Type: Grant
    Filed: January 2, 2020
    Date of Patent: February 23, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Lisa F. Edge, Hemanth Jagannathan, Paul C. Jamison, Vamsi K. Paruchuri
  • Patent number: 10930567
    Abstract: A method is presented for forming a transistor having reduced parasitic contact resistance. The method includes forming a first device over a semiconductor structure, forming a second device adjacent the first device, forming an ILD over the first and second devices, and forming recesses within the ILD to expose the source/drain regions of the first device and the source/drain regions of the second device. The method further includes forming a first dielectric layer over the ILD and the top surfaces of the source/drain regions of the first and second devices, a chemical interaction between the first dielectric layer and the source/drain regions of the second device resulting in second dielectric layers formed over the source/drain regions of the second device, and forming an epitaxial layer over the source/drain regions of the first device after removing remaining portions of the first dielectric layer.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: February 23, 2021
    Assignee: International Business Machines Corporation
    Inventors: Choonghyun Lee, Shogo Mochizuki, Chun Wing Yeung, Hemanth Jagannathan
  • Patent number: 10916432
    Abstract: Methods are provided to form pure silicon oxide layers on silicon-germanium (SiGe) layers, as well as an FET device having a pure silicon oxide interfacial layer of a metal gate structure formed on a SiGe channel layer of the FET device. For example, a method comprises growing a first silicon oxide layer on a surface of a SiGe layer using a first oxynitridation process, wherein the first silicon oxide layer comprises nitrogen. The first silicon oxide layer is removed, and a second silicon oxide layer is grown on the surface of the SiGe layer using a second oxynitridation process, which is substantially the same as the first oxynitridation process, wherein the second silicon oxide layer is substantially devoid of germanium oxide and nitrogen. For example, the first silicon oxide layer comprises a SiON layer and the second silicon oxide layer comprises a pure silicon dioxide layer.
    Type: Grant
    Filed: August 15, 2019
    Date of Patent: February 9, 2021
    Assignee: International Business Machines Corporation
    Inventors: Takashi Ando, Pouya Hashemi, Hemanth Jagannathan, ChoongHyun Lee, Vijay Narayanan
  • Publication number: 20210035867
    Abstract: A vertical field effect transistor structure and method for fabricating the same. The structure includes a source/drain layer in contact with at least one semiconductor fin. An edge portion of the source/drain layer includes a notched region filled with a dielectric material. A spacer layer includes a first portion in contact with the source/drain layer and a second portion in contact with the dielectric material. A gate structure contacts the spacer layer and the dielectric material. The method includes forming a source/drain layer in contact with at least one semiconductor fin. A spacer layer is formed in contact with the source/drain layer. A portion of the spacer layer is removed to expose an end portion of the source/drain layer. The exposed end portion of the source/drain layer is recessed to form a notched region within the source/drain layer. A dielectric layer is formed within the notched region.
    Type: Application
    Filed: August 1, 2019
    Publication date: February 4, 2021
    Inventors: Ruilong Xie, Hemanth JAGANNATHAN, Christopher J. WASKIEWICZ, Alexander REZNICEK