Patents by Inventor Pranita Kulkarni

Pranita Kulkarni 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: 8871582
    Abstract: One method includes forming a recessed gate/spacer structure that partially defines a spacer/gate cap recess, forming a gate cap layer in the spacer/gate cap recess, forming a gate cap protection layer on an upper surface of the gate cap layer, and removing portions of the gate cap protection layer, leaving a portion of the gate cap protection layer positioned on the upper surface of the gate cap layer. A device disclosed herein includes a gate/spacer structure positioned in a layer of insulating material, a gate cap layer positioned on the gate/spacer structure, wherein sidewalls of the gate cap layer contact the layer of insulating material, and a gate cap protection layer positioned on an upper surface of the gate cap layer, wherein the sidewalls of the gate cap protection layer also contact the layer of insulating material.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 28, 2014
    Assignees: GLOBALFOUNDRIES Inc., International Business Machines Corporation
    Inventors: Daniel Pham, Xiuyu Cai, Balasubramanian Pranatharthiharan, Pranita Kulkarni
  • Patent number: 8860107
    Abstract: At least one semiconductor fin for a capacitor is formed concurrently with other semiconductor fins for field effect transistors. A lower conductive layer is deposited and lithographically patterned to form a lower conductive plate located on the at least one semiconductor fin. A dielectric layer and at least one upper conductive layer are formed and lithographically patterned to form a node dielectric and an upper conductive plate over the lower conductive plate as well as a gate dielectric and a gate conductor over the other semiconductor fins. The lower conductive plate, the node dielectric, and the upper conductive plate collectively form a capacitor. The finFETs may be dual gate finFETs or trigate finFETs. A buried insulator layer may be optionally recessed to increase the capacitance. Alternately, the lower conductive plate may be formed on a planar surface of the buried insulator layer.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: October 14, 2014
    Assignee: International Business Machines Corporation
    Inventors: Wilfried E. Haensch, Pranita Kulkarni, Tenko Yamashita
  • Patent number: 8860138
    Abstract: A method of forming a transistor device includes forming a patterned gate structure over a semiconductor substrate; forming a spacer layer over the semiconductor substrate and patterned gate structure; removing horizontally disposed portions of the spacer layer so as to form a vertical sidewall spacer adjacent the patterned gate structure; and forming a raised source/drain (RSD) structure over the semiconductor substrate and adjacent the vertical sidewall spacer, wherein the RSD structure has a substantially vertical sidewall profile so as to abut the vertical sidewall spacer and produce one of a compressive and a tensile strain on a channel region of the semiconductor substrate below the patterned gate structure.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: October 14, 2014
    Assignee: International Business Machines Corporation
    Inventors: Bruce B. Doris, Kangguo Cheng, Ali Khakifirooz, Pranita Kulkarni, Ghavam G. Shahidi
  • Patent number: 8853038
    Abstract: A gate stack is formed on a silicon layer that is above a buried oxide layer. The gate stack comprises a high-k oxide layer on the silicon layer and a metal gate on the high-k oxide layer. A first nitride layer is formed on the silicon layer and the gate stack. An oxide layer is formed on the first nitride layer. A second nitride layer is formed on the oxide layer. The first nitride layer and the oxide layer are etched so as to form a nitride liner and an oxide liner adjacent to the gate stack. The second nitride layer is etched so as to form a first nitride spacer adjacent to the oxide liner. A faceted raised source/drain region is epitaxially formed adjacent to the nitride liner, the oxide liner, and first nitride spacer. Ions are implanted into the faceted raised source/drain region using the first nitride spacer.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: October 7, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce Doris, Ali Khakifirooz, Pranita Kulkarni, Ghavam Shahidi
  • Publication number: 20140264486
    Abstract: One method includes forming a recessed gate/spacer structure that partially defines a spacer/gate cap recess, forming a gate cap layer in the spacer/gate cap recess, forming a gate cap protection layer on an upper surface of the gate cap layer, and removing portions of the gate cap protection layer, leaving a portion of the gate cap protection layer positioned on the upper surface of the gate cap layer. A device disclosed herein includes a gate/spacer structure positioned in a layer of insulating material, a gate cap layer positioned on the gate/spacer structure, wherein sidewalls of the gate cap layer contact the layer of insulating material, and a gate cap protection layer positioned on an upper surface of the gate cap layer, wherein the sidewalls of the gate cap protection layer also contact the layer of insulating material.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION, GLOBALFOUNDRIES INC.
    Inventors: Daniel Pham, Xiuyu Cai, Balasubramanian Pranatharthiharan, Pranita Kulkarni
  • Publication number: 20140264487
    Abstract: One method disclosed herein includes forming first and second gate cap protection layers that encapsulate and protect a gate cap layer. A novel transistor device disclosed herein includes a gate structure positioned above a semiconductor substrate, a spacer structure positioned adjacent the gate structure, a layer of insulating material positioned above the substrate and around the spacer structure, a gate cap layer positioned above the gate structure and the spacer structure, and a gate cap protection material that encapsulates the gate cap layer, wherein portions of the gate cap protection material are positioned between the gate cap layer and the gate structure, the spacer structure and the layer of insulating material.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicants: International Business Machines Corporation, GLOBALFOUNDRIES Inc.
    Inventors: Daniel Pham, Xiuyu Cai, Balasubramanian Pranatharthiharan, Pranita Kulkarni
  • Patent number: 8835330
    Abstract: A method includes providing a substrate having an N+ type layer; forming a P type region in the N+ type layer disposed within the N+ type layer; forming a first deep trench isolation structure extending through a silicon layer and into the N+ type layer to a depth that is greater than a depth of the P type layer; forming a dynamic RAM FET in the silicon layer, forming a first logic/static RAM FET in the silicon layer above the P type region, the P type region being functional as a P-type back gate of the first logic/static RAM FET; and forming a first contact through the silicon layer and an insulating layer to electrically connect to the N+ type layer and a second contact through the silicon layer and the insulating layer to electrically connect to the P type region.
    Type: Grant
    Filed: September 19, 2012
    Date of Patent: September 16, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Chen, Bruce B. Doris, Terence B. Hook, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8835900
    Abstract: A floating body memory cell, memory circuit, and method for fabricating floating body memory cells. The floating body memory cell includes a bi-layer heterojunction having a first semiconductor coupled to a second semiconductor. The first semiconductor and the second semiconductor have different energy band gaps. The floating body memory cell includes a buried insulator layer. The floating body memory cell includes a back transistor gate separated from the second semiconductor of the bi-layer heterojunction by at least the buried insulated layer. The floating body memory cell also includes a front transistor gate coupled to the first semiconductor of the bi-layer heterojunction.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: September 16, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ali Khakifirooz, Pranita Kulkarni, Ghavam G. Shahidi
  • Patent number: 8803233
    Abstract: A transistor includes a semiconductor layer, and a gate dielectric is formed on the semiconductor layer. A gate conductor is formed on the gate dielectric and an active area is located in the semiconductor layer underneath the gate dielectric. The active area includes a graded dopant region that has a higher doping concentration near a top surface of the semiconductor layer and a lower doping concentration near a bottom surface of the semiconductor layer. This graded dopant region has a gradual decrease in the doping concentration. The transistor also includes source and drain regions that are adjacent to the active region. The source and drain regions and the active area have the same conductivity type.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: August 12, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Ali Khakifirooz, Pranita Kulkarni, Tak H. Ning
  • Patent number: 8785273
    Abstract: A method of manufacturing a FinFET non-volatile memory device and a FinFET non-volatile memory device structure. A substrate is provided and a layer of semiconductor material is deposited over the substrate. A hard mask is deposited over the semiconductor material and the structure is patterned to form fins. A charge storage layer is deposited over the structure, including the fins and the portions of it are damaged using an angled ion implantation process. The damaged portions are removed and gate structures are formed on either side of the fin, with only one side having a charge storage layer.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: July 22, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8742508
    Abstract: A three dimensional FET device structure which includes a plurality of three dimensional FET devices. Each of the three dimensional FET devices include an insulating base, a three dimensional fin oriented perpendicular to the insulating base, a gate dielectric wrapped around the three dimensional fin and a gate wrapped around the gate dielectric and extending perpendicularly to the three dimensional fin, the three dimensional fin having a device width being defined as the circumference of the three dimensional fin in contact with the gate dielectric. At least a first of the three dimensional FET devices has a first device width while at least a second of the three dimensional FET devices has a second device width. The first device width is different than the second device width. Also included is a method of making the three dimensional FET device structure.
    Type: Grant
    Filed: July 16, 2011
    Date of Patent: June 3, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8742485
    Abstract: In one exemplary embodiment of the invention, a method includes: providing an inversion mode varactor having a substrate, a backgate layer overlying the substrate, an insulating layer overlying the backgate layer, a semiconductor layer overlying the insulating layer and at least one metal-oxide semiconductor field effect transistor (MOSFET) device disposed upon the semiconductor layer, where the semiconductor layer includes a source region and a drain region, where the at least one MOSFET device includes a gate stack defining a channel between the source region and the drain region, where the gate stack has a gate dielectric layer overlying the semiconductor layer and a conductive layer overlying the gate dielectric layer; and applying a bias voltage to the backgate layer to form an inversion region in the semiconductor layer at an interface between the semiconductor layer and the insulating layer.
    Type: Grant
    Filed: October 23, 2013
    Date of Patent: June 3, 2014
    Assignee: International Business Machines Corporation
    Inventors: Bruce B. Doris, Kangguo Cheng, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8710588
    Abstract: A semiconductor device and a method of fabricating a semiconductor device are disclosed. In one embodiment, the method comprises providing a semiconductor substrate, epitaxially growing a Ge layer on the substrate, and epitaxially growing a semiconductor layer on the Ge layer, where the semiconductor layer has a thickness of 10 nm or less. This method further comprises removing at least a portion of the Ge layer to form a void beneath the Si layer, and filling the void at least partially with a dielectric material. In this way, the semiconductor layer becomes an extremely thin semiconductor-on-insulator layer. In one embodiment, after the void is filled with the dielectric material, in-situ doped source and drain regions are grown on the semiconductor layer. In one embodiment, the method further comprises annealing said source and drain regions to form doped extension regions in the semiconductor layer.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: April 29, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Dechao Guo, Pranita Kulkarni, Philip J. Oldiges, Ghavam G. Shahidi
  • Patent number: 8691650
    Abstract: MOSFETs and methods for making MOSFETs with a recessed channel and abrupt junctions are disclosed. The method includes creating source and drain extensions while a dummy gate is in place. The source/drain extensions create a diffuse junction with the silicon substrate. The method continues by removing the dummy gate and etching a recess in the silicon substrate. The recess intersects at least a portion of the source and drain junction. Then a channel is formed by growing a silicon film to at least partially fill the recess. The channel has sharp junctions with the source and drains, while the unetched silicon remaining below the channel has diffuse junctions with the source and drain. Thus, a MOSFET with two junction regions, sharp and diffuse, in the same transistor can be created.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: April 8, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce Doris, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8685804
    Abstract: Transistor devices including stressors are disclosed. One such transistor device includes a channel region, a dielectric layer and a semiconductor substrate. The channel region is configured to provide a conductive channel between a source region and a drain region. In addition, the dielectric layer is below the channel region and is configured to electrically insulate the channel region. Further, the semiconductor substrate, which is below the channel region and below the dielectric layer, includes dislocation defects at a top surface of the semiconductor substrate, where the dislocation defects are collectively oriented to impose a compressive strain on the channel region such that charge carrier mobility is enhanced in the channel region.
    Type: Grant
    Filed: October 3, 2011
    Date of Patent: April 1, 2014
    Assignee: International Business Machines Corporation
    Inventors: Stephen W. Bedell, Kangguo Cheng, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8680628
    Abstract: In one exemplary embodiment of the invention, a semiconductor structure includes: a substrate; and a plurality of devices at least partially overlying the substrate, where the plurality of devices include a first device coupled to a second device via a first raised source/drain having a first length, where the first device is further coupled to a second raised source/drain having a second length, where the first device comprises a transistor, where the first raised source/drain and the second raised source/drain at least partially overly the substrate, where the second raised source/drain comprises a terminal electrical contact, where the second length is greater than the first length.
    Type: Grant
    Filed: October 19, 2012
    Date of Patent: March 25, 2014
    Assignee: International Business Machines Corporation
    Inventors: Bruce B. Doris, Kangguo Cheng, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8673699
    Abstract: A method of forming a semiconductor structure which includes an extremely thin silicon-on-insulator (ETSOI) semiconductor structure having a PFET portion and an NFET portion, a gate structure in the PFET portion and the NFET portion, a high quality nitride spacer adjacent to the gate structures in the PFET portion and the NFET portion and a doped faceted epitaxial silicon germanium raised source/drain (RSD) in the PFET portion. An amorphous silicon layer is formed on the RSD in the PFET portion. A faceted epitaxial silicon RSD is formed on the ETSOI adjacent to the high quality nitride in the NFET portion. The amorphous layer in the PFET portion prevents epitaxial growth in the PFET portion during formation of the RSD in the NFET portion. Extensions are ion implanted into the ETSOI underneath the gate structure in the NFET portion.
    Type: Grant
    Filed: July 17, 2012
    Date of Patent: March 18, 2014
    Assignee: International Business Machines Corporation
    Inventors: Thomas N. Adam, Kangguo Cheng, Bruce B. Doris, Bala S. Haran, Pranita Kulkarni, Amlan Majumdar, Stefan Schmitz
  • Patent number: 8673738
    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: Grant
    Filed: June 25, 2012
    Date of Patent: March 18, 2014
    Assignee: International Business Machines Corporation
    Inventors: Bruce B. Doris, Kangguo Cheng, Balasubramanian S. Haran, Ali Khakifirooz, Pranita Kulkarni, Arvind Kumar, Shom Ponoth
  • Patent number: 8664050
    Abstract: A structure and method to improve ETSOI MOSFET devices. A wafer is provided including regions with at least a first semiconductor layer overlying an oxide layer overlying a second semiconductor layer. The regions are separated by a STI which extends at least partially into the second semiconductor layer and is partially filled with a dielectric. A gate structure is formed over the first semiconductor layer and during the wet cleans involved, the STI divot erodes until it is at a level below the oxide layer. Another dielectric layer is deposited over the device and a hole is etched to reach source and drain regions. The hole is not fully landed, extending at least partially into the STI, and an insulating material is deposited in said hole.
    Type: Grant
    Filed: March 20, 2012
    Date of Patent: March 4, 2014
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Bruce B. Doris, Balasubramanian S. Haran, Ali Khakifirooz, Pranita Kulkarni
  • Patent number: 8658505
    Abstract: Multigate transistor devices and methods of their fabrication are disclosed. In accordance with one method, a fin and a gate structure that is disposed on a plurality of surfaces of the fin are formed. In addition, at least a portion of an extension of the fin is removed to form a recessed portion that is below the gate structure, is below a channel region of the fin, and includes at least one angled indentation. Further, a terminal extension is grown in the at least one angled indentation below the channel region and along a surface of the channel region such that the terminal extension provides a stress on the channel region to enhance charge carrier mobility in the channel region.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: February 25, 2014
    Assignee: International Business Machines Corporation
    Inventors: Ming Cai, Dechao Guo, Pranita Kulkarni, Chun-Chen Yeh