Patents by Inventor Balasubramanian S. Haran

Balasubramanian S. Haran 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: 8836031
    Abstract: After formation of raised source and drain regions, a conformal dielectric material liner is deposited within recessed regions formed by removal of shallow trench isolation structures and underlying portions of a buried insulator layer in a semiconductor-on-insulator (SOI) substrate. A dielectric material that is different from the material of the conformal dielectric material liner is subsequently deposited and planarized to form a planarized dielectric material layer. The planarized dielectric material layer is recessed selective to the conformal dielectric material liner to form dielectric fill portions that fill the recessed regions. Horizontal portions of the conformal dielectric material liner are removed by an anisotropic etch, while remaining portions of the conformal dielectric material liner form an outer gate spacer. At least one contact-level dielectric layer is deposited. Contact via structures electrically isolated from a handle substrate can be formed within the contact via holes.
    Type: Grant
    Filed: November 13, 2013
    Date of Patent: September 16, 2014
    Assignee: International Business Machines Corporation
    Inventors: Balasubramanian S. Haran, David V. Horak, Charles W. Koburger, III, Shom Ponoth
  • Patent number: 8828828
    Abstract: At least one drain-side surfaces of a field effect transistor (FET) structure, which can be a structure for a planar FET or a fin FET, is structurally damaged by an angled ion implantation of inert or electrically active dopants, while at least one source-side surface of the transistor is protected from implantation by a gate stack and a gate spacer. Epitaxial growth of a semiconductor material is retarded on the at least one structurally damaged drain-side surface, while epitaxial growth proceeds without retardation on the at least one source-side surface. A raised epitaxial source region has a greater thickness than a raised epitaxial drain region, thereby providing an asymmetric FET having lesser source-side external resistance than drain-side external resistance, and having lesser drain-side overlap capacitance than source-side overlap capacitance.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: September 9, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Patent number: 8829617
    Abstract: A method including providing a plurality of fins etched from a semiconductor substrate and covered by an oxide layer and a nitride layer, the oxide layer being located between the plurality of fins and the nitride layer, removing a portion of the plurality of fins to form an opening, and forming a dielectric spacer on a sidewall of the opening. The method may also include filling the opening with a fill material, wherein a top surface of the fill material is substantially flush with a top surface of the nitride layer, removing the nitride layer to form a gap between the plurality of fins and the fill material, wherein the fill material has re-entrant geometry extending over the gap, and removing the re-entrant geometry and causing the gap between the plurality of fins and the fill material to widen.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: September 9, 2014
    Assignee: International Business Machines Corporation
    Inventors: Balasubramanian S. Haran, Sanjay Mehta, Shom Ponoth, Ravikumar Ramachandran, Stefan Schmitz, Theodorus E. Standaert
  • Patent number: 8815694
    Abstract: Embodiments include semiconductor-on-insulator (SOI) substrates having SOI layers strained by oxidation of the base substrate layer and methods of forming the same. The method may include forming a strained channel region in a semiconductor-on-insulator (SOI) substrate including a buried insulator (BOX) layer above a base substrate layer and a SOI layer above the BOX layer by first etching the SOI layer and the BOX layer to form a first isolation recess region and a second isolation recess region. A portion of the SOI layer between the first isolation recess region and the second isolation recess region defines a channel region in the SOI layer. A portion of the base substrate layer below the first isolation recess region and below the second isolation recess region may then be oxidized to form a first oxide region and a second oxide region, respectively, that apply compressive strain to the channel region.
    Type: Grant
    Filed: December 3, 2012
    Date of Patent: August 26, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Balasubramanian S. Haran, Ali Khakifirooz, Pranita Kerber
  • Patent number: 8796128
    Abstract: A structure and method for forming a dual metal fill and dual threshold voltage for replacement gate metal devices is disclosed. A selective deposition process involving titanium and aluminum is used to allow formation of two adjacent transistors with different fill metals and different workfunction metals, enabling different threshold voltages in the adjacent transistors.
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: August 5, 2014
    Assignee: International Business Machines Corporation
    Inventors: Lisa F. Edge, Nathaniel Berliner, James John Demarest, Balasubramanian S. Haran, Raymond J. Donohue
  • Patent number: 8790991
    Abstract: A shallow trench isolation region is provided in which void formation is substantially or totally eliminated therefrom. The shallow trench isolation mitigates active shorts between two active regions of a semiconductor substrate. The shallow trench isolation region includes a bilayer liner which is present on sidewalls and a bottom wall of a trench that is formed in a semiconductor substrate. The bilayer liner of the present disclosure includes, from bottom to top, a shallow trench isolation liner, e.g., a semiconductor oxide and/or nitride, and a high k liner, e.g., a dielectric material having a dielectric constant that is greater than silicon oxide.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: July 29, 2014
    Assignee: International Business Machines Corporation
    Inventors: Jason E. Cummings, Balasubramanian S. Haran, Hemanth Jagannathan, Sanjay Mehta
  • Publication number: 20140191321
    Abstract: An improved finFET and method of fabrication using a silicon-on-nothing process flow is disclosed. Nitride spacers protect the fin sides during formation of cavities underneath the fins for the silicon-on-nothing (SON) process. A flowable oxide fills the cavities to form an insulating dielectric layer under the fins.
    Type: Application
    Filed: January 9, 2013
    Publication date: July 10, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus Eduardus Standaert, Tenko Yamashita
  • Patent number: 8772874
    Abstract: At least one drain-side surfaces of a field effect transistor (FET) structure, which can be a structure for a planar FET or a fin FET, is structurally damaged by an angled ion implantation of inert or electrically active dopants, while at least one source-side surface of the transistor is protected from implantation by a gate stack and a gate spacer. Epitaxial growth of a semiconductor material is retarded on the at least one structurally damaged drain-side surface, while epitaxial growth proceeds without retardation on the at least one source-side surface. A raised epitaxial source region has a greater thickness than a raised epitaxial drain region, thereby providing an asymmetric FET having lesser source-side external resistance than drain-side external resistance, and having lesser drain-side overlap capacitance than source-side overlap capacitance.
    Type: Grant
    Filed: August 24, 2011
    Date of Patent: July 8, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140187007
    Abstract: At least one drain-side surfaces of a field effect transistor (FET) structure, which can be a structure for a planar FET or a fin FET, is structurally damaged by an angled ion implantation of inert or electrically active dopants, while at least one source-side surface of the transistor is protected from implantation by a gate stack and a gate spacer. Epitaxial growth of a semiconductor material is retarded on the at least one structurally damaged drain-side surface, while epitaxial growth proceeds without retardation on the at least one source-side surface. A raised epitaxial source region has a greater thickness than a raised epitaxial drain region, thereby providing an asymmetric FET having lesser source-side external resistance than drain-side external resistance, and having lesser drain-side overlap capacitance than source-side overlap capacitance.
    Type: Application
    Filed: March 7, 2014
    Publication date: July 3, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140175549
    Abstract: A method for fabricating a field effect transistor device includes removing a portion of a first semiconductor layer and a first insulator layer to expose a portion of a second semiconductor layer, wherein the second semiconductor layer is disposed on a second insulator layer, the first insulator layer is disposed on the second semiconductor layer, and the first semiconductor layer is disposed on the first insulator layer, removing portions of the first semiconductor layer to form a first fin disposed on the first insulator layer and removing portions of the second semiconductor layer to form a second fin disposed on the second insulator layer, and forming a first gate stack over a portion of the first fin and forming a second gate stack over a portion of the second fin.
    Type: Application
    Filed: February 26, 2014
    Publication date: June 26, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140159123
    Abstract: A method including providing fins etched from a semiconductor substrate, the fins covered by an oxide layer and a nitride layer, the oxide layer located between the fins and the nitride layer, removing a portion of the fins to form an opening, and forming a spacer on a sidewall of the opening. The method further including filling the opening above the semiconductor substrate with a first fill material, where a top surface of the fill material is substantially flush with a top surface of the nitride layer, removing the spacer to expose a vertical sidewall of the first fill material, and depositing an encapsulation layer conformally on top of the first fill material, where the encapsulation layer is resistant to wet etching techniques and protects from the unwanted removal of the first fill material during subsequent process techniques.
    Type: Application
    Filed: December 7, 2012
    Publication date: June 12, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140162447
    Abstract: A method for fabricating a field effect transistor device includes patterning a fin on substrate, patterning a gate stack over a portion of the fin and a portion of an insulator layer arranged on the substrate, forming a protective barrier over the gate stack, a portion of the fin and a portion of the insulator layer, the protective barrier enveloping the gate stack, depositing a second insulator layer over portions of the fin and the protective barrier, performing a first etching process to selectively remove portions of the second insulator layer to define cavities that expose portions of source and drain regions of the fin without appreciably removing the protective barrier, and depositing a conductive material in the cavities.
    Type: Application
    Filed: December 10, 2012
    Publication date: June 12, 2014
    Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION, RENESAS ELECTRONICS CORPORATION, GLOBALFOUNDRIES, INC.
    Inventors: Lisa F. Edge, Martin M. Frank, Balasubramanian S. Haran, Atsuro Inada, Sivananda K. Kanakasabapathy, Andreas Knorr, Vijay Narayanan, Vamsi K. Paruchuri, Soon-cheon Seo
  • Publication number: 20140154865
    Abstract: Shallow trench isolation structures are provided for use with UTBB (ultra-thin body and buried oxide) semiconductor substrates, which prevent defect mechanisms from occurring, such as the formation of electrical shorts between exposed portions of silicon layers on the sidewalls of shallow trench of a UTBB substrate, in instances when trench fill material of the shallow trench is subsequently etched away and recessed below an upper surface of the UTBB substrate.
    Type: Application
    Filed: February 5, 2014
    Publication date: June 5, 2014
    Applicant: International Business Machines Corporation
    Inventors: Bruce B. Doris, Kangguo Cheng, Balasubramanian S. Haran, Ali Khakifirooz, Pranita Kerber, Arvind Kumar, Shom Ponoth
  • Publication number: 20140151801
    Abstract: A method including providing a plurality of fins etched from a semiconductor substrate and covered by an oxide layer and a nitride layer, the oxide layer being located between the plurality of fins and the nitride layer, removing a portion of the plurality of fins to form an opening, and forming a dielectric spacer on a sidewall of the opening. The method may also include filling the opening with a fill material, wherein a top surface of the fill material is substantially flush with a top surface of the nitride layer, removing the nitride layer to form a gap between the plurality of fins and the fill material, wherein the fill material has re-entrant geometry extending over the gap, and removing the re-entrant geometry and causing the gap between the plurality of fins and the fill material to widen.
    Type: Application
    Filed: November 30, 2012
    Publication date: June 5, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Balasubramanian S. Haran, Sanjay Mehta, Shom Ponoth, Ravikumar Ramachandran, Stefan Schmitz, Theodorus E. Standaert
  • Publication number: 20140145247
    Abstract: A method for fabricating a field effect transistor (FET) device includes forming a plurality of semiconductor fins on a substrate, removing a semiconductor fin of the plurality of semiconductor fins from a portion of the substrate, forming an isolation fin that includes a dielectric material on the substrate on the portion of the substrate, and forming a gate stack over the plurality of semiconductor fins and the isolation fin.
    Type: Application
    Filed: November 26, 2012
    Publication date: May 29, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Ali Khakifirooz, Shom Ponoth, Theodorus E. Strandaert, Tenko Yamashita
  • Publication number: 20140145248
    Abstract: FinFET structures with dielectric fins and methods of fabrication are disclosed. A gas cluster ion beam (GCIB) tool is used to apply an ion beam to exposed fins, which converts the fins from a semiconductor material such as silicon, to a dielectric such as silicon nitride or silicon oxide. Unlike some prior art techniques, where some fins are removed prior to fin merging, in embodiments of the present invention, fins are not removed. Instead, semiconductor (silicon) fins are converted to dielectric (nitride/oxide) fins where it is desirable to have isolation between groups of fins that comprise various finFET devices on an integrated circuit (IC).
    Type: Application
    Filed: November 26, 2012
    Publication date: May 29, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Ali Khakifirooz, Shom Ponoth, Theodorus Eduardus Standaert, Tenko Yamashita
  • Publication number: 20140117421
    Abstract: A metallic top surface of a replacement gate structure is oxidized to convert a top portion of the replacement gate structure into a dielectric oxide. After removal of a planarization dielectric layer, selective epitaxy is performed to form a raised source region and a raised drain region that extends higher than the topmost surface of the replacement gate structure. A gate level dielectric layer including a first dielectric material is deposited and subsequently planarized employing the raised source and drain regions as stopping structures. A contact level dielectric layer including a second dielectric material is formed over the gate level dielectric layer, and contact via holes are formed employing an etch chemistry that etches the second dielectric material selective to the first dielectric material. Raised source and drain regions are recessed. Self-aligned contact structures can be formed by filling the contact via holes with a conductive material.
    Type: Application
    Filed: October 31, 2012
    Publication date: May 1, 2014
    Applicant: International Business Machines Corporation
    Inventors: Soon-Cheon Seo, Balasubramanian S. Haran, Alexander Reznicek
  • Patent number: 8703553
    Abstract: Methods for capacitor fabrication include doping a capacitor region of a semiconductor layer in a semiconductor-on-insulator substrate; partially etching the semiconductor layer to produce a first terminal layer comprising doped semiconductor fins on a remaining base of doped semiconductor; forming a dielectric layer over the first terminal layer; and forming a second terminal layer over the dielectric layer in a finFET process.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: April 22, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140103450
    Abstract: A substrate including a handle substrate, a lower insulator layer, a buried semiconductor layer, an upper insulator layer, and a top semiconductor layer is provided. Semiconductor fins can be formed by patterning a portion of the buried semiconductor layer after removal of the upper insulator layer and the top semiconductor layer in a fin region, while a planar device region is protected by an etch mask. A disposable fill material portion is formed in the fin region, and a shallow trench isolation structure can be formed in the planar device region. The disposable fill material portion is removed, and gate stacks for a planar field effect transistor and a fin field effect transistor can be simultaneously formed. Alternately, disposable gate structures and a planarization dielectric layer can be formed, and replacement gate stacks can be subsequently formed.
    Type: Application
    Filed: October 12, 2012
    Publication date: April 17, 2014
    Applicant: International Business Machines Corporation
    Inventors: Kangguo Cheng, Balasubramanian S. Haran, Shom Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20140084382
    Abstract: A structure and method for forming a dual metal fill and dual threshold voltage for replacement gate metal devices is disclosed. A selective deposition process involving titanium and aluminum is used to allow formation of two adjacent transistors with different fill metals and different workfunction metals, enabling different threshold voltages in the adjacent transistors.
    Type: Application
    Filed: November 26, 2013
    Publication date: March 27, 2014
    Applicant: International Business Machines Corporation
    Inventors: Nathaniel Berliner, James John Demarest, Lisa F. Edge, Balasubramanian S. Haran