Patents by Inventor Amlan Majumdar

Amlan Majumdar 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: 9287362
    Abstract: An approach to forming a semiconductor structure for a vertical field effect transistor with a controlled gate overlap. The approach includes forming on a semiconductor substrate, a first semiconductor layer, a second semiconductor layer, a third semiconductor layer, a fourth semiconductor layer, a fifth semiconductor layer, and a first dielectric layer. The etched first dielectric layer and a first drain contact are surrounded by a first spacer. The first drain contact is composed of the fifth semiconductor layer. A second drain contact composed of the fourth semiconductor layer, a channel composed of the third semiconductor layer, and a second source contact composed of the second semiconductor layer are formed. Additionally, first source contact composed of the first semiconductor is formed and a gate electrode is formed on a portion of the first source contact layer surrounding a portion of the first pillar and the second pillar.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: March 15, 2016
    Assignee: International Business Machines Corporation
    Inventors: Anirban Basu, Cheng-Wei Cheng, Wilfried E. Haensch, Amlan Majumdar, Kuen-Ting Shiu
  • Patent number: 9287115
    Abstract: A method of forming a semiconductor substrate including a type III-V semiconductor material directly on a dielectric material that includes forming a trench in a dielectric layer, and forming a via within the trench extending from a base of the trench to an exposed upper surface of an underlying semiconductor including substrate. A III-V semiconductor material is formed extending from the exposed upper surface of the semiconductor substrate filling at least a portion of the trench.
    Type: Grant
    Filed: March 12, 2014
    Date of Patent: March 15, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cheng-Wei Cheng, Edward W. Kiewra, Amlan Majumdar, Uzma Rana, Devendra K. Sadana, Kuen-Ting Shiu, Yanning Sun
  • Patent number: 9263260
    Abstract: A semiconductor device comprising a suspended semiconductor nanowire inner gate and outer gate. A first epitaxial dielectric layer surrounds a nanowire inner gate. The first epitaxial dielectric layer is surrounded by an epitaxial semiconductor channel. The epitaxial semiconductor channel surrounds a second dielectric layer. A gate conductor surrounds the second dielectric layer. The gate conductor is patterned into a gate line and defines a channel region overlapping the gate line. The semiconductor device contains source and drain regions adjacent to the gate line.
    Type: Grant
    Filed: December 16, 2014
    Date of Patent: February 16, 2016
    Assignee: International Business Machines Corporation
    Inventors: Anirban Basu, Guy M. Cohen, Amlan Majumdar, Jeffrey W. Sleight
  • Patent number: 9224866
    Abstract: A semiconductor fin including a vertical stack, from bottom to top, of a second semiconductor material and a first semiconductor material is formed on a substrate. A disposable gate structure straddling the semiconductor fin is formed. A source region and a drain region are formed employing the disposable gate structure as an implantation mask, At least one semiconductor shell layer or a semiconductor cap layer can be formed as an etch stop structure. A planarization dielectric layer is subsequently formed. A gate cavity is formed by removing the disposable gate structure. A portion of the second semiconductor material is removed selective to the first semiconductor material within the gate cavity so that a middle portion of the semiconductor fin becomes suspended over the substrate. A gate dielectric layer and a gate electrode are sequentially formed. The gate electrode laterally surrounds a body region of a fin field effect transistor.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: December 29, 2015
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Anirban Basu, Guy Cohen, Amlan Majumdar, Jeffrey W. Sleight
  • Patent number: 9196711
    Abstract: Fin mask structures are formed over a semiconductor material portion on a crystalline insulator layer. A disposable gate structure and a gate spacer are formed over the fin mask structures. Employing the disposable gate structure and the gate spacer as an etch mask, physically exposed portions of the fin mask structures and the semiconductor material portion are removed by an etch. A source region and a drain region are formed by selective epitaxy of a semiconductor material from physically exposed surfaces of the crystalline insulator layer. The disposable gate structure is removed selective to the source region and the drain region. Semiconductor fins are formed by anisotropically etching portions of the semiconductor material portion, employing the gate spacer and the fin mask structures as etch masks. A gate dielectric and a gate electrode are formed within the gate cavity.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: November 24, 2015
    Assignee: International Business Machines Corporation
    Inventors: Anirban Basu, Guy M. Cohen, Amlan Majumdar
  • Publication number: 20150325650
    Abstract: A method including forming a pair of inner spacers along a vertical sidewall of a gate trench, gate trench extending into a III-V compound semiconductor-containing heterostructure, forming a gate conductor within the gate trench, removing a portion of a first dielectric layer selective to the gate conductor and the pair of inner spacers, forming a pair of outer spacers adjacent to the pair of inner spacers, the outer spacers are in direct contact with and self-aligned to the inner spacers, and forming a pair of source-drain contacts within an uppermost layer of the III-V compound semiconductor-containing heterostructure, the pair of source-drain contacts are self-aligned to the pair of outer spacers such that an edge of each individual source-drain contact is aligned with an outside edge of each individual outer spacer.
    Type: Application
    Filed: July 8, 2015
    Publication date: November 12, 2015
    Inventors: Anirban Basu, Amlan Majumdar, Kuen-Ting Shiu, Yanning Sun
  • Patent number: 9178061
    Abstract: A method is provided for fabricating a semiconductor device. According to the method, a semiconductor layer is formed over a semiconductor-on-insulator substrate, and a gate is formed on the semiconductor layer. Source and drain extension regions and a deep drain region are formed in the semiconductor layer. A deep source region is formed in the semiconductor layer. A drain metal-semiconductor alloy contact is located on the upper portion of the deep drain region and abutting the drain extension region. A source metal-semiconductor alloy contact abuts the source extension region. The deep source region is located below and contacts a first portion of the source metal-semiconductor alloy contact. The deep source region is not located below and does not contact a second portion of the source metal-semiconductor alloy contact. The second portion of the source metal-semiconductor alloy contact is an internal body contact that directly contacts the semiconductor layer.
    Type: Grant
    Filed: August 10, 2012
    Date of Patent: November 3, 2015
    Assignee: GLOBALFOUNDRIES INC
    Inventors: Jin Cai, Steven J. Koester, Amlan Majumdar
  • Publication number: 20150311302
    Abstract: A disposable gate structure straddling a semiconductor fin is formed. A source region and a drain region are formed employing the disposable gate structure as an implantation mask. A planarization dielectric layer is formed such that a top surface of the planarization dielectric layer is coplanar with the disposable gate structure. A gate cavity is formed by removing the disposable gate structure. An epitaxial cap layer is deposited on physically exposed semiconductor surfaces of the semiconductor fin by selective epitaxy. A gate dielectric layer is formed on the epitaxial cap layer, and a gate electrode can be formed by filling the gate cavity. The epitaxial cap layer can include a material that reduces the density of interfacial defects at an interface with the gate dielectric layer.
    Type: Application
    Filed: June 15, 2015
    Publication date: October 29, 2015
    Inventors: Anirban Basu, Guy Cohen, Amlan Majumdar
  • Patent number: 9159822
    Abstract: A method including forming a pair of inner spacers along a vertical sidewall of a gate trench, gate trench extending into a III-V compound semiconductor-containing heterostructure, forming a gate conductor within the gate trench, removing a portion of a first dielectric layer selective to the gate conductor and the pair of inner spacers, forming a pair of outer spacers adjacent to the pair of inner spacers, the outer spacers are in direct contact with and self-aligned to the inner spacers, and forming a pair of source-drain contacts within an uppermost layer of the III-V compound semiconductor-containing heterostructure, the pair of source-drain contacts are self-aligned to the pair of outer spacers such that an edge of each individual source-drain contact is aligned with an outside edge of each individual outer spacer.
    Type: Grant
    Filed: February 24, 2014
    Date of Patent: October 13, 2015
    Assignee: International Business Machines Corporation
    Inventors: Anirban Basu, Amlan Majumdar, Kuen-Ting Shiu, Yanning Sun
  • Publication number: 20150287600
    Abstract: Techniques for forming dual III-V semiconductor channel materials to enable fabrication of different device types on the same chip/wafer are provided. In one aspect, a method of forming dual III-V semiconductor channel materials on a wafer includes the steps of: providing a wafer having a first III-V semiconductor layer on an oxide; forming a second III-V semiconductor layer on top of the first III-V semiconductor layer, wherein the second III-V semiconductor layer comprises a different material with an electron affinity that is less than an electron affinity of the first III-V semiconductor layer; converting the first III-V semiconductor layer in at least one second active area to an insulator using ion implantation; and removing the second III-V semiconductor layer from at least one first active area selective to the first III-V semiconductor layer.
    Type: Application
    Filed: April 7, 2014
    Publication date: October 8, 2015
    Applicant: International Business Machines Corporation
    Inventors: Josephine B. Chang, Isaac Lauer, Amlan Majumdar, Jeffrey W. Sleight
  • Publication number: 20150263102
    Abstract: A structure and method for forming a substrate, a buffer layer disposed on the substrate, an oxide layer disposed on the buffer layer, and a fin comprising a semiconductor material disposed on the oxide layer.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 17, 2015
    Applicant: International Business Machines Corporation
    Inventors: Anirban Basu, Guy M. Cohen, Amlan Majumdar, Yu Zhu
  • Publication number: 20150262818
    Abstract: A method of forming a semiconductor substrate including a type III-V semiconductor material directly on a dielectric material that includes forming a trench in a dielectric layer, and forming a via within the trench extending from a base of the trench to an exposed upper surface of an underlying semiconductor including substrate. A III-V semiconductor material is formed extending from the exposed upper surface of the semiconductor substrate filling at least a portion of the trench.
    Type: Application
    Filed: March 12, 2014
    Publication date: September 17, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cheng-Wei Cheng, Edward W. Kiewra, Amlan Majumdar, Uzma Rana, Devendra K. Sadana, Kuen-Ting Shiu, Yanning Sun
  • Patent number: 9136357
    Abstract: A method for fabricating a multigate device includes forming a fin on a substrate of the multigate device, the fin being formed of a semiconductor material, growing a first conformal epitaxial layer directly on the fin and substrate, wherein the first conformal epitaxial layer is undoped or lightly doped, growing a second conformal epitaxial layer directly on the first conformal epitaxial layer, wherein the second conformal epitaxial layer is highly doped, selectively removing a portion of the second epitaxial layer to expose a portion of the first conformal epitaxial layer and thereby form a trench, and forming a gate within the trench.
    Type: Grant
    Filed: March 5, 2014
    Date of Patent: September 15, 2015
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Anirban Basu, Guy Cohen, Amlan Majumdar
  • Publication number: 20150255568
    Abstract: A method for fabricating a multigate device includes forming a fin on a substrate of the multigate device, the fin being formed of a semiconductor material, growing a first conformal epitaxial layer directly on the fin and substrate, wherein the first conformal epitaxial layer is undoped or lightly doped, growing a second conformal epitaxial layer directly on the first conformal epitaxial layer, wherein the second conformal epitaxial layer is highly doped, selectively removing a portion of the second epitaxial layer to expose a portion of the first conformal epitaxial layer and thereby form a trench, and forming a gate within the trench.
    Type: Application
    Filed: March 5, 2014
    Publication date: September 10, 2015
    Applicant: International Business Machines Corporation
    Inventors: ANIRBAN BASU, Guy Cohen, Amlan Majumdar
  • Publication number: 20150255567
    Abstract: A method for fabricating a multigate device includes forming a fin on a substrate of the multigate device, the fin being formed of a semiconductor material, growing a first conformal epitaxial layer directly on the fin and substrate, wherein the first conformal epitaxial layer is highly doped, growing a second conformal epitaxial layer directly on the first conformal epitaxial layer, wherein the second conformal epitaxial layer is highly doped, selectively removing a portion of second epitaxial layer to expose a portion of the first conformal epitaxial layer, selectively removing a portion of the first conformal epitaxial layer to expose a portion of the fin and thereby form a trench, and forming a gate within the trench.
    Type: Application
    Filed: March 5, 2014
    Publication date: September 10, 2015
    Applicant: International Business Machines Corporation
    Inventors: Anirban Basu, Guy Cohen, Amlan Majumdar
  • Publication number: 20150255460
    Abstract: Embodiments for the present invention provide a CMOS structure and methods for fabrication. In an embodiment of the present invention, a CMOS structure comprises a NFET, formed on a wafer, having a gate stack and a channel. A PFET having a gate stack and a channel is also formed on the wafer. The channel of the PFET and the channel of the NFET include semiconductor material formed on III-V semiconductor material, such that the III-V semiconductor material acts like a buried oxide because of a valence band offset between the semiconductor material and the III-V material. There is a height difference between a terminal of the NFET and a terminal of the PFET. In addition, the gate stack NFET is the same height as the gate stack PFET.
    Type: Application
    Filed: March 6, 2014
    Publication date: September 10, 2015
    Applicant: International Business Machines Corporation
    Inventors: Cheng-wei Cheng, Amlan Majumdar, Kuen-Ting Shiu
  • Publication number: 20150255570
    Abstract: Fin mask structures are formed over a semiconductor material portion on a crystalline insulator layer. A disposable gate structure and a gate spacer are formed over the fin mask structures. Employing the disposable gate structure and the gate spacer as an etch mask, physically exposed portions of the fin mask structures and the semiconductor material portion are removed by an etch. A source region and a drain region are formed by selective epitaxy of a semiconductor material from physically exposed surfaces of the crystalline insulator layer. The disposable gate structure is removed selective to the source region and the drain region. Semiconductor fins are formed by anisotropically etching portions of the semiconductor material portion, employing the gate spacer and the fin mask structures as etch masks. A gate dielectric and a gate electrode are formed within the gate cavity.
    Type: Application
    Filed: March 7, 2014
    Publication date: September 10, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Anirban Basu, Guy M. Cohen, Amlan Majumdar
  • Patent number: 9123569
    Abstract: Embodiments for the present invention provide a CMOS structure and methods for fabrication. In an embodiment of the present invention, a CMOS structure comprises a NFET, formed on a wafer, having a gate stack and a channel. A PFET having a gate stack and a channel is also formed on the wafer. The channel of the PFET and the channel of the NFET include semiconductor material formed on III-V semiconductor material, such that the III-V semiconductor material acts like a buried oxide because of a valence band offset between the semiconductor material and the III-V material. There is a height difference between a terminal of the NFET and a terminal of the PFET. In addition, the gate stack NFET is the same height as the gate stack PFET.
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: September 1, 2015
    Assignee: International Business Machines Corporation
    Inventors: Cheng-wei Cheng, Amlan Majumdar, Kuen-Ting Shiu
  • Publication number: 20150243773
    Abstract: A method including forming a pair of inner spacers along a vertical sidewall of a gate trench, gate trench extending into a III-V compound semiconductor-containing heterostructure, forming a gate conductor within the gate trench, removing a portion of a first dielectric layer selective to the gate conductor and the pair of inner spacers, forming a pair of outer spacers adjacent to the pair of inner spacers, the outer spacers are in direct contact with and self-aligned to the inner spacers, and forming a pair of source-drain contacts within an uppermost layer of the III-V compound semiconductor-containing heterostructure, the pair of source-drain contacts are self-aligned to the pair of outer spacers such that an edge of each individual source-drain contact is aligned with an outside edge of each individual outer spacer.
    Type: Application
    Filed: February 24, 2014
    Publication date: August 27, 2015
    Applicant: International Business Machines Corporation
    Inventors: Anirban Basu, Amlan Majumdar, Kuen-Ting Shiu, Yanning Sun
  • Patent number: 9105482
    Abstract: A nanowire tunnel device includes a nanowire suspended above a semiconductor substrate by a first pad region and a second pad region, the nanowire having a channel portion surrounded by a gate structure disposed circumferentially around the nanowire, an n-type doped region including a first portion of the nanowire adjacent to the channel portion, and a p-type doped region including a second portion of the nanowire adjacent to the channel portion.
    Type: Grant
    Filed: July 24, 2012
    Date of Patent: August 11, 2015
    Assignee: International Business Machines Corporation
    Inventors: Sarunya Bangsaruntip, Stephen J. Koester, Amlan Majumdar, Jeffrey W. Sleights