Patents by Inventor Prasanna Khare

Prasanna Khare 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).

  • Publication number: 20180145133
    Abstract: Channel-to-substrate leakage in a FinFET device is prevented by inserting an insulating layer between the semiconducting channel and the substrate during fabrication of the device. Similarly, source/drain-to-substrate leakage in a FinFET device is prevented by isolating the source/drain regions from the substrate by inserting an insulating layer between the source/drain regions and the substrate. Forming such an insulating layer isolates the conduction path from the substrate both physically and electrically, thus preventing current leakage. In an array of semiconducting fins made up of a multi-layer stack, the bottom material is removed thus yielding a fin array that is suspended above the silicon surface. A resulting gap underneath the remaining top fin material is then filled with oxide to better support the fins and to isolate the array of fins from the substrate.
    Type: Application
    Filed: January 17, 2018
    Publication date: May 24, 2018
    Inventors: Nicolas LOUBET, Prasanna KHARE
  • Publication number: 20180068902
    Abstract: A method for co-integrating finFETs of two semiconductor material types, e.g., Si and SiGe, on a bulk substrate is described. Fins for finFETs may be formed in an epitaxial layer of a first semiconductor type, and covered with an insulator. A portion of the fins may be removed to form voids in the insulator, and the voids may be filled by epitaxially growing a semiconductor material of a second type in the voids. The co-integrated finFETs may be formed at a same device level.
    Type: Application
    Filed: November 14, 2017
    Publication date: March 8, 2018
    Inventors: Nicolas Loubet, Prasanna Khare, Qing Liu
  • Patent number: 9905662
    Abstract: A method of making a semiconductor device includes forming a fin mask layer on a semiconductor layer, forming a dummy gate over the fin mask layer, and forming source and drain regions on opposite sides of the dummy gate. The dummy gate is removed and the underlying fin mask layer is used to define a plurality of fins in the semiconductor layer. A gate is formed over the plurality of fins.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: February 27, 2018
    Assignee: STMICROELECTRONICS, INC.
    Inventors: Nicolas Loubet, Prasanna Khare
  • Patent number: 9893147
    Abstract: Channel-to-substrate leakage in a FinFET device is prevented by inserting an insulating layer between the semiconducting channel and the substrate during fabrication of the device. Similarly, source/drain-to-substrate leakage in a FinFET device is prevented by isolating the source/drain regions from the substrate by inserting an insulating layer between the source/drain regions and the substrate. Forming such an insulating layer isolates the conduction path from the substrate both physically and electrically, thus preventing current leakage. In an array of semiconducting fins made up of a multi-layer stack, the bottom material is removed thus yielding a fin array that is suspended above the silicon surface. A resulting gap underneath the remaining top fin material is then filled with oxide to better support the fins and to isolate the array of fins from the substrate.
    Type: Grant
    Filed: November 7, 2016
    Date of Patent: February 13, 2018
    Assignee: STMICROELECTRONICS, INC.
    Inventors: Nicolas Loubet, Prasanna Khare
  • Patent number: 9847260
    Abstract: A method for co-integrating finFETs of two semiconductor material types, e.g., Si and SiGe, on a bulk substrate is described. Fins for finFETs may be formed in an epitaxial layer of a first semiconductor type, and covered with an insulator. A portion of the fins may be removed to form voids in the insulator, and the voids may be filled by epitaxially growing a semiconductor material of a second type in the voids. The co-integrated finFETs may be formed at a same device level.
    Type: Grant
    Filed: December 15, 2015
    Date of Patent: December 19, 2017
    Assignee: STMICROELECTRONICS, INC.
    Inventors: Nicolas Loubet, Prasanna Khare, Qing Liu
  • Patent number: 9793378
    Abstract: Improved fin field effect transistor (FinFET) devices and methods for fabrication thereof. In one aspect, a method for fabricating a FinFET device comprises: a silicon substrate on which a silicon epitaxial layer is grown is provided. Sacrificial structures on the substrate are formed from the epitaxial layer. A blanket silicon layer is formed over the sacrificial structures and exposed substrate portions, the blanket silicon layer having upper and lower portions of uniform thickness and intermediate portions interposed between the upper and lower portions of non-uniform thickness and having an angle of formation. An array of semiconducting fins is formed from the blanket silicon layer and a non-conformal layer formed over the blanket layer. The sacrificial structures are removed and the resulting void filled with isolation structures under the channel regions. Source and drain are formed in the source/drain regions during a fin merge of the FinFET.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: October 17, 2017
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: Nicolas Loubet, Shom Ponoth, Prasanna Khare, Qing Liu, Balasubramanian Pranatharthiharan
  • Patent number: 9768055
    Abstract: An electronic device may include a substrate, a buried oxide (BOX) layer overlying the substrate, at least one semiconductor device overlying the BOX layer, and at least one shallow trench isolation (STI) region in the substrate and adjacent the at least one semiconductor device. The at least one STI region defines a sidewall surface with the substrate and may include an oxide layer lining a bottom portion of the sidewall surface, a nitride layer lining a top portion of the sidewall surface above the bottom portion, and an insulating material within the nitride and oxide layers.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: September 19, 2017
    Assignees: STMICROELECTRONICS, INC., INTERNATIONAL BUSINESS MACHINES CORPORATION, COMMISSASRIAT À L'ÉNERGIE ATOMIQUE ET AUX ÉNERGIES ALTERNATIVES, (CEA)
    Inventors: Qing Liu, Nicolas Loubet, Prasanna Khare, Shom Ponoth, Maud Vinet, Bruce Doris
  • Publication number: 20170179137
    Abstract: An improved transistor with channel epitaxial silicon. In one aspect, a method of fabrication includes: forming a gate stack structure on an epitaxial silicon region disposed on a substrate, a width dimension of the epitaxial silicon region approximating a width dimension of the gate stack structure; and growing a raised epitaxial source and drain from the substrate, the raised epitaxial source and drain in contact with the epitaxial silicon region and the gate stack structure. For a SRAM device, further: removing an epitaxial layer in contact with the silicon substrate and the raised source and drain and to which the epitaxial silicon region is coupled leaving a space above the silicon substrate and under the raised epitaxial source and drain; and filling the space with an insulating layer and isolating the raised epitaxial source and drain and a channel of the transistor from the silicon substrate.
    Type: Application
    Filed: March 3, 2017
    Publication date: June 22, 2017
    Inventors: STEPHANE ALLEGRET-MARET, KANGGUO CHENG, BRUCE DORIS, PRASANNA KHARE, QING LIU, NICOLAS LOUBET
  • Patent number: 9685380
    Abstract: A method for co-integrating finFETs of two semiconductor material types, e.g., Si and SiGe, on a bulk substrate is described. Fins for finFETs may be formed in an epitaxial layer of a first semiconductor type, and covered with an insulator. A portion of the fins may be removed to form voids in the insulator, and the voids may be filled by epitaxially growing a semiconductor material of a second type in the voids. The co-integrated finFETs may be formed at a same device level.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: June 20, 2017
    Assignee: STMICROELECTRONICS, INC.
    Inventors: Nicolas Loubet, Prasanna Khare, Qing Liu
  • Publication number: 20170170299
    Abstract: An improved transistor with channel epitaxial silicon and methods for fabrication thereof. In one aspect, a method for fabricating a transistor includes: forming a gate stack structure on an epitaxial silicon region, a width dimension of the epitaxial silicon region approximating a width dimension of the gate stack structure; encapsulating the epitaxial silicon region under the gate stack structure with sacrificial spacers formed on both sides of the gate stack structure and the epitaxial silicon region; forming a channel of the transistor having a width dimension that approximates that of the epitaxial silicon region and the gate stack structure, the epitaxial silicon region and the gate stack structure formed on the channel of the transistor; removing the sacrificial spacers; and growing a raised epitaxial source and drain from the silicon substrate, with portions of the raised epitaxial source and drain in contact with the epitaxial silicon region.
    Type: Application
    Filed: February 21, 2017
    Publication date: June 15, 2017
    Inventors: STEPHANE ALLEGRET-MARET, KANGGUO CHENG, BRUCE DORIS, PRASANNA KHARE, QING LIU, NICOLAS LOUBET
  • Patent number: 9673222
    Abstract: Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
    Type: Grant
    Filed: May 17, 2016
    Date of Patent: June 6, 2017
    Assignees: GLOBALFOUNDRIES Inc., STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: Ajey Poovannummoottil Jacob, Kangguo Cheng, Bruce Doris, Nicolas Loubet, Prasanna Khare, Rama Divakaruni
  • Patent number: 9620507
    Abstract: An improved transistor with channel epitaxial silicon and methods for fabrication thereof. In one aspect, a method for fabricating a transistor includes: forming a gate stack structure on an epitaxial silicon region, a width dimension of the epitaxial silicon region approximating a width dimension of the gate stack structure; encapsulating the epitaxial silicon region under the gate stack structure with sacrificial spacers formed on both sides of the gate stack structure and the epitaxial silicon region; forming a channel of the transistor having a width dimension that approximates that of the epitaxial silicon region and the gate stack structure, the epitaxial silicon region and the gate stack structure formed on the channel of the transistor; removing the sacrificial spacers; and growing a raised epitaxial source and drain from the silicon substrate, with portions of the raised epitaxial source and drain in contact with the epitaxial silicon region.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: April 11, 2017
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: Nicolas Loubet, Qing Liu, Prasanna Khare, Stephane Allegret-Maret, Bruce Doris, Kangguo Cheng
  • Patent number: 9620506
    Abstract: An improved transistor with channel epitaxial silicon. In one aspect, a method of fabrication includes: forming a gate stack structure on an epitaxial silicon region disposed on a substrate, a width dimension of the epitaxial silicon region approximating a width dimension of the gate stack structure; and growing a raised epitaxial source and drain from the substrate, the raised epitaxial source and drain in contact with the epitaxial silicon region and the gate stack structure. For a SRAM device, further: removing an epitaxial layer in contact with the silicon substrate and the raised source and drain and to which the epitaxial silicon region is coupled leaving a space above the silicon substrate and under the raised epitaxial source and drain; and filling the space with an insulating layer and isolating the raised epitaxial source and drain and a channel of the transistor from the silicon substrate.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: April 11, 2017
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: Nicolas Loubet, Qing Liu, Prasanna Khare, Stephane Allegret-Maret, Bruce Doris, Kangguo Cheng
  • Publication number: 20170053981
    Abstract: Channel-to-substrate leakage in a FinFET device is prevented by inserting an insulating layer between the semiconducting channel and the substrate during fabrication of the device. Similarly, source/drain-to-substrate leakage in a FinFET device is prevented by isolating the source/drain regions from the substrate by inserting an insulating layer between the source/drain regions and the substrate. Forming such an insulating layer isolates the conduction path from the substrate both physically and electrically, thus preventing current leakage. In an array of semiconducting fins made up of a multi-layer stack, the bottom material is removed thus yielding a fin array that is suspended above the silicon surface. A resulting gap underneath the remaining top fin material is then filled with oxide to better support the fins and to isolate the array of fins from the substrate.
    Type: Application
    Filed: November 7, 2016
    Publication date: February 23, 2017
    Inventors: Nicolas LOUBET, Prasanna KHARE
  • Publication number: 20170040427
    Abstract: A method of making a semiconductor device includes forming a fin mask layer on a semiconductor layer, forming a dummy gate over the fin mask layer, and forming source and drain regions on opposite sides of the dummy gate. The dummy gate is removed and the underlying fin mask layer is used to define a plurality of fins in the semiconductor layer. A gate is formed over the plurality of fins.
    Type: Application
    Filed: October 21, 2016
    Publication date: February 9, 2017
    Inventors: Nicolas LOUBET, Prasanna KHARE
  • Patent number: 9520393
    Abstract: Channel-to-substrate leakage in a FinFET device can be prevented by inserting an insulating layer between the semiconducting channel and the substrate. Similarly, source/drain-to-substrate leakage in a FinFET device can be prevented by isolating the source/drain regions from the substrate by inserting an insulating layer between the source/drain regions and the substrate. The insulating layer isolates the conduction path from the substrate both physically and electrically, thus preventing current leakage. If an array of semiconducting fins is made up of a multi-layer stack, the bottom material can be removed thus yielding a fin array that is suspended above the silicon surface. A resulting gap underneath the remaining top fin material can then be filled in with oxide to better support the fins and to isolate the array of fins from the substrate. The resulting FinFET device is fully substrate-isolated in both the gate region and the source/drain regions.
    Type: Grant
    Filed: December 31, 2014
    Date of Patent: December 13, 2016
    Assignee: STMICROELECTRONICS, INC.
    Inventors: Nicolas Loubet, Prasanna Khare
  • Patent number: 9502292
    Abstract: A shallow trench is formed to extend into a handle substrate of a semiconductor-on-insulator (SOI) layer. A dielectric liner stack of a dielectric metal oxide layer and a silicon nitride layer is formed in the shallow trench, followed by deposition of a shallow trench isolation fill portion. The dielectric liner stack is removed from above a top surface of a top semiconductor portion, followed by removal of a silicon nitride pad layer and an upper vertical portion of the dielectric metal oxide layer. A divot laterally surrounding a stack of a top semiconductor portion and a buried insulator portion is filled with a silicon nitride portion. Gate structures and source/drain structures are subsequently formed. The silicon nitride portion or the dielectric metal oxide layer functions as a stopping layer during formation of source/drain contact via holes, thereby preventing electrical shorts between source/drain contact via structures and the handle substrate.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: November 22, 2016
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, STMicroelectronics, Inc., COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
    Inventors: Bruce B. Doris, Shom Ponoth, Prasanna Khare, Qing Liu, Nicolas Loubet, Maud Vinet
  • Publication number: 20160322356
    Abstract: A multi-fin FINFET device may include a substrate and a plurality of semiconductor fins extending upwardly from the substrate and being spaced apart along the substrate. Each semiconductor fin may have opposing first and second ends and a medial portion therebetween, and outermost fins of the plurality of semiconductor fins may comprise an epitaxial growth barrier on outside surfaces thereof. The FINFET may further include at least one gate overlying the medial portions of the semiconductor fins, a plurality of raised epitaxial semiconductor source regions between the semiconductor fins adjacent the first ends thereof, and a plurality of raised epitaxial semiconductor drain regions between the semiconductor fins adjacent the second ends thereof.
    Type: Application
    Filed: July 13, 2016
    Publication date: November 3, 2016
    Inventors: Qing LIU, Prasanna KHARE, Nicolas LOUBET
  • Publication number: 20160260742
    Abstract: Methods and semiconductor structures formed from the methods are provided which facilitate fabricating semiconductor fin structures. The methods include, for example: providing a wafer with at least one semiconductor fin extending above a substrate; transforming a portion of the semiconductor fin(s) into an isolation layer, the isolation layer separating a semiconductor layer of the semiconductor fin(s) from the substrate; and proceeding with forming a fin device(s) of a first architectural type in a first fin region of the semiconductor fin(s), and a fin device(s) of a second architectural type in a second fin region of the semiconductor fin(s), where the first architectural type and the second architectural type are different fin device architectures.
    Type: Application
    Filed: May 17, 2016
    Publication date: September 8, 2016
    Applicants: GLOBALFOUNDRIES Inc., STMICROELECTRONICS, INC.
    Inventors: Ajey Poovannummoottil JACOB, Kangguo CHENG, Bruce DORIS, Nicolas LOUBET, Prasanna KHARE, Rama DIVAKARUNI
  • Patent number: 9437504
    Abstract: On a first semiconductor material substrate, an overlying sacrificial layer formed of a second semiconductor material is deposited. In a first region, a first semiconductor material region is formed over the sacrificial layer. In a second region, a second semiconductor material region is formed over the sacrificial layer. The first semiconductor material region is patterned to define a first FinFET fin. The second semiconductor material region is patterned to define a second FinFET fin. The fins are each covered with a cap and sidewall spacer. The sacrificial layer formed of the second semiconductor material is then selectively removed to form an opening below each of the first and second FinFET fins (with those fins being supported by the sidewall spacers). The openings below each of the fins are then filled with a dielectric material that serves to isolate the semiconductive materials of the fins from the substrate.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: September 6, 2016
    Assignees: STMicroelectronics, Inc., International Business Machines Corporation
    Inventors: Nicolas Loubet, Prasanna Khare, Qing Liu, Balasubramanian Pranatharthiharan, Shom Ponoth