Patents by Inventor Ramachandra Divakaruni

Ramachandra Divakaruni 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: 9312360
    Abstract: A semiconductor device is provided that includes a pedestal of an insulating material present over at least one layer of a semiconductor material, and at least one fin structure in contact with the pedestal of the insulating material. Source and drain region structures are present on opposing sides of the at least one fin structure. At least one of the source and drain region structures includes at least two epitaxial material layers. A first epitaxial material layer is in contact with the at least one layer of semiconductor material. A second epitaxial material layer is in contact with the at least one fin structure. The first epitaxial material layer is separated from the at least one fin structure by the second epitaxial material layer. A gate structure present on the at least one fin structure.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: April 12, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Alexander Reznicek, Soon-Cheon Seo
  • Patent number: 9305930
    Abstract: A flash memory device in a dual fin single floating gate configuration is provided. Semiconductor fins are formed on a stack of a back gate conductor layer and a back gate dielectric layer. Pairs of semiconductor fins are formed in an array environment such that shallow trench isolation structures can be formed along the lengthwise direction of the semiconductor fins within the array. After formation of tunneling dielectrics on the sidewalls of the semiconductor fins, a floating gate electrode is formed between each pair of proximally located semiconductor fins by deposition of a conformal conductive material layer and an isotropic etch. A control gate dielectric and a control gate electrode are formed by deposition and patterning of a dielectric layer and a conductive material layer.
    Type: Grant
    Filed: December 11, 2013
    Date of Patent: April 5, 2016
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Ramachandra Divakaruni, Arvind Kumar, Carl J. Radens
  • Patent number: 9263454
    Abstract: Embodiments for the present invention provide a semiconductor device and methods for fabrication. In an embodiment of the present invention, a semiconductor structure comprises a first conductor horizontally formed on a semiconductor substrate. A second conductor is vertically formed in a semiconductor stack that includes the semiconductor substrate. An oxidized region is formed proximate to the first conductor. The second conductor is formed in a manner to be in electrical communication with the first conductor. The first conductor is formed in a manner to be laterally connected to the second conductor. The first conductor is formed in a manner to not traverse beneath the oxidized region. The first conductor is formed in a manner to have a reduced link-up resistance with adjacent epitaxial material included in the semiconductor structure.
    Type: Grant
    Filed: August 27, 2015
    Date of Patent: February 16, 2016
    Assignee: International Business Machines Corporation
    Inventors: Emre Alptekin, Pooja R. Batra, Kangguo Cheng, Ramachandra Divakaruni, Johnathan E. Faltermeier, Reinaldo A. Vega
  • Patent number: 9263449
    Abstract: A method of forming a semiconductor structure within a semiconductor substrate is provided. The method may include forming, on the substrate, a first group of fins associated with a first device; a second group of fins associated with a second device; and a third group of fins located between the first group of fins and the second group of fins, whereby the third group of fins are associated with a third device. A shallow trench isolation (STI) region is formed between the first and the second group of fins by recessing the third group of fins into an opening within the substrate, such that the recessed third group of fins includes a fin top surface that is located below a top surface of the substrate. The top surface of the substrate is substantially coplanar with a fin bottom surface corresponding to the first and second group of fins.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: February 16, 2016
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Theodorus E. Standaert
  • Patent number: 9245892
    Abstract: Embodiments for the present invention provide a semiconductor device and methods for fabrication. In an embodiment of the present invention, a semiconductor structure comprises a first conductor horizontally formed on a semiconductor substrate. A second conductor is vertically formed in a semiconductor stack that includes the semiconductor substrate. An oxidized region is formed proximate to the first conductor. The second conductor is formed in a manner to be in electrical communication with the first conductor. The first conductor is formed in a manner to be laterally connected to the second conductor. The first conductor is formed in a manner to not traverse beneath the oxidized region. The first conductor is formed in a manner to have a reduced link-up resistance with adjacent epitaxial material included in the semiconductor structure.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: January 26, 2016
    Assignee: International Business Machines Corporation
    Inventors: Emre Alptekin, Pooja R. Batra, Kangguo Cheng, Ramachandra Divakaruni, Johnathan E. Faltermeier, Reinaldo A. Vega
  • Patent number: 9245981
    Abstract: An array of stacks containing a semiconductor fins and an oxygen-impermeable cap is formed on a semiconductor substrate with a substantially uniform areal density. Oxygen-impermeable spacers are formed around each stack, and the semiconductor substrate is etched to vertically extend trenches. Semiconductor sidewalls are physically exposed from underneath the oxygen-impermeable spacers. The oxygen-impermeable spacers are removed in regions in which semiconductor fins are not needed. A dielectric oxide material is deposited to fill the trenches. Oxidation is performed to convert a top portion of the semiconductor substrate and semiconductor fins not protected by oxygen-impermeable spacers into dielectric material portions. Upon removal of the oxygen-impermeable caps and remaining oxygen-impermeable spacers, an array including semiconductor fins and dielectric fins is provided.
    Type: Grant
    Filed: July 24, 2015
    Date of Patent: January 26, 2016
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Bruce B. Doris, Ali Khakifirooz, Edward J. Nowak, Kern Rim
  • Patent number: 9236389
    Abstract: After forming a plurality of gate structures over a substrate having a plurality of active regions separated from each other by at least one shallow trench isolation (STI) regions, inter-gate dielectric contact structures extending through an interlevel dielectric (ILD) layer that surrounds the gate structures are formed. Each inter-gate dielectric contact structure encloses a corresponding gate structure and is in contact with a dielectric gate cap and a dielectric gate spacer of the corresponding gate structure and a portion of the at least one STI region abutting the dielectric gate spacer of the corresponding gate structure. The inter-gate dielectric contact structure is electrically insulated from a gate conductor in the corresponding gate structure by the dielectric gate cap and the dielectric gate spacer and serves as a control gate in a memory cell of a flash memory array.
    Type: Grant
    Filed: August 12, 2014
    Date of Patent: January 12, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Subramanian S. Iyer, Ali Khakifirooz
  • Publication number: 20150380438
    Abstract: The present invention relates generally to semiconductor devices and more particularly, to a structure and method of forming a high-mobility fin field effect transistor (finFET) fin in a silicon semiconductor on insulator (SOI) substrate by trapping crystalline lattice dislocations that occur during epitaxial growth in a recess formed in a semiconductor layer. The crystalline lattice dislocations may remain trapped below a thin isolation layer, thereby reducing device thickness and the need for high-aspect ratio etching and fin formation.
    Type: Application
    Filed: June 26, 2014
    Publication date: December 31, 2015
    Inventors: Michael P. Chudzik, Ramachandra Divakaruni, Judson R. Holt, Arvind Kumar, Unoh Kwon
  • Patent number: 9224654
    Abstract: Spacer structures are formed around an array of disposable mandrel structures and above a doped semiconductor material portion. A sidewall image transfer process is employed to pattern an upper portion of the doped semiconductor material portion into an array of doped semiconductor fins. After formation of a dielectric material layer on the top surfaces and sidewall surfaces of the doped semiconductor fins, gate-level mandrel structures are formed to straddle multiple semiconductor fins. A conductive hole-containing structure is formed to laterally surround a plurality of gate-level mandrel structures, which is subsequently removed. A contact-level dielectric layer is formed over the conductive hole-containing structure and the plurality of doped semiconductor fins. The semiconductor fins function as a lower electrode of a fin capacitor, and the conductive hole-containing structure functions as an upper electrode of the fin capacitor.
    Type: Grant
    Filed: November 25, 2013
    Date of Patent: December 29, 2015
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Shom S. Ponoth, Theodorus E. Standaert, Tenko Yamashita
  • Publication number: 20150364476
    Abstract: Embodiments for the present invention provide a semiconductor device and methods for fabrication. In an embodiment of the present invention, a semiconductor structure comprises a first conductor horizontally formed on a semiconductor substrate. A second conductor is vertically formed in a semiconductor stack that includes the semiconductor substrate. An oxidized region is formed proximate to the first conductor. The second conductor is formed in a manner to be in electrical communication with the first conductor. The first conductor is formed in a manner to be laterally connected to the second conductor. The first conductor is formed in a manner to not traverse beneath the oxidized region. The first conductor is formed in a manner to have a reduced link-up resistance with adjacent epitaxial material included in the semiconductor structure.
    Type: Application
    Filed: August 27, 2015
    Publication date: December 17, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Emre Alptekin, Pooja R. Batra, Kangguo Cheng, Ramachandra Divakaruni, Johnathan E. Faltermeier, Reinaldo A. Vega
  • Publication number: 20150357331
    Abstract: A method of forming a semiconductor structure within a semiconductor substrate is provided. The method may include forming, on the substrate, a first group of fins associated with a first device; a second group of fins associated with a second device; and a third group of fins located between the first group of fins and the second group of fins, whereby the third group of fins are associated with a third device. A shallow trench isolation (STI) region is formed between the first and the second group of fins by recessing the third group of fins into an opening within the substrate, such that the recessed third group of fins includes a fin top surface that is located below a top surface of the substrate. The top surface of the substrate is substantially coplanar with a fin bottom surface corresponding to the first and second group of fins.
    Type: Application
    Filed: August 19, 2015
    Publication date: December 10, 2015
    Applicant: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Theodorus E. Standaert
  • Patent number: 9209094
    Abstract: A first fin field effect transistor and a second fin field effect transistor are formed on an insulator layer overlying a semiconductor material layer. A first pair of trenches is formed through the insulator layer in regions in which a source region and a drain region of the first fin field effect transistor is to be formed. A second pair of trenches is formed partly into the insulator layer without extending to the top surface of the semiconductor material layer. The source region and the drain region of the first field effect transistor can be epitaxial stressor material portions that are anchored to, and epitaxially aligned to, the semiconductor material layer and apply stress to the channel of the first field effect transistor to enhance performance. The insulator layer provides electrical isolation from the semiconductor material layer to the second field effect transistor.
    Type: Grant
    Filed: July 29, 2013
    Date of Patent: December 8, 2015
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Kern Rim
  • Patent number: 9209172
    Abstract: A method of forming a semiconductor structure within a semiconductor substrate is provided. The method may include forming, on the substrate, a first group of fins associated with a first device; a second group of fins associated with a second device; and a third group of fins located between the first group of fins and the second group of fins, whereby the third group of fins are associated with a third device. A shallow trench isolation (STI) region is formed between the first and the second group of fins by recessing the third group of fins into an opening within the substrate, such that the recessed third group of fins includes a fin top surface that is located below a top surface of the substrate. The top surface of the substrate is substantially coplanar with a fin bottom surface corresponding to the first and second group of fins.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: December 8, 2015
    Assignee: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Theodorus E. Standaert
  • Publication number: 20150340294
    Abstract: Embodiments of the present invention provide methods and structures by which the inherent discretization of effective width can be relaxed through introduction of a fractional effective device width, thereby allowing greater flexibility for design applications, such as SRAM design optimization. A portion of some fins are clad with a capping layer or workfunction material to change the threshold voltage (Vt) for a part of the fin, rendering that part of the fin electrically inactive, which changes the effective device width (Weff). Other fins are unclad, and provide maximum area of constant threshold voltage. In this way, the effective device width of some devices is reduced. Therefore, the effective device width is controllable by controlling the level of cladding of the fin.
    Type: Application
    Filed: May 21, 2014
    Publication date: November 26, 2015
    Applicant: International Business Machines Corporation
    Inventors: Ramachandra Divakaruni, Arvind Kumar, Carl John Radens
  • Publication number: 20150333156
    Abstract: An array of stacks containing a semiconductor fins and an oxygen-impermeable cap is formed on a semiconductor substrate with a substantially uniform areal density. Oxygen-impermeable spacers are formed around each stack, and the semiconductor substrate is etched to vertically extend trenches. Semiconductor sidewalls are physically exposed from underneath the oxygen-impermeable spacers. The oxygen-impermeable spacers are removed in regions in which semiconductor fins are not needed. A dielectric oxide material is deposited to fill the trenches. Oxidation is performed to convert a top portion of the semiconductor substrate and semiconductor fins not protected by oxygen-impermeable spacers into dielectric material portions. Upon removal of the oxygen-impermeable caps and remaining oxygen-impermeable spacers, an array including semiconductor fins and dielectric fins is provided.
    Type: Application
    Filed: July 24, 2015
    Publication date: November 19, 2015
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Bruce B. Doris, Ali Khakifirooz, Edward J. Nowak, Kern Rim
  • Patent number: 9190520
    Abstract: A fin structure includes an optional doped well, a disposable single crystalline semiconductor material portion, and a top semiconductor portion formed on a substrate. A disposable gate structure straddling the fin structure is formed, and end portions of the fin structure are removed to form end cavities. Doped semiconductor material portions are formed on sides of a stack of the disposable single crystalline semiconductor material portion and a channel region including the top semiconductor portion. The disposable single crystalline semiconductor material portion may be replaced with a dielectric material portion after removal of the disposable gate structure or after formation of the stack. The gate cavity is filled with a gate dielectric and a gate electrode. The channel region is stressed by the doped semiconductor material portions, and is electrically isolated from the substrate by the dielectric material portion.
    Type: Grant
    Filed: September 9, 2014
    Date of Patent: November 17, 2015
    Assignee: GLOBALFOUNDRIES INC.
    Inventors: Henry K. Utomo, Kangguo Cheng, Ramachandra Divakaruni, Dechao Guo, Myung-Hee Na, Ravikumar Ramachandran, Kern Rim, Huiling Shang
  • Publication number: 20150325572
    Abstract: A method of forming a semiconductor structure within a semiconductor substrate is provided. The method may include forming, on the substrate, a first group of fins associated with a first device; a second group of fins associated with a second device; and a third group of fins located between the first group of fins and the second group of fins, whereby the third group of fins are associated with a third device. A shallow trench isolation (STI) region is formed between the first and the second group of fins by recessing the third group of fins into an opening within the substrate, such that the recessed third group of fins includes a fin top surface that is located below a top surface of the substrate. The top surface of the substrate is substantially coplanar with a fin bottom surface corresponding to the first and second group of fins.
    Type: Application
    Filed: May 8, 2014
    Publication date: November 12, 2015
    Applicant: International Business Machines Corporation
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Theodorus E. Standaert
  • Publication number: 20150318377
    Abstract: A semiconductor device is provided that includes a pedestal of an insulating material present over at least one layer of a semiconductor material, and at least one fin structure in contact with the pedestal of the insulating material. Source and drain region structures are present on opposing sides of the at least one fin structure. At least one of the source and drain region structures includes at least two epitaxial material layers. A first epitaxial material layer is in contact with the at least one layer of semiconductor material. A second epitaxial material layer is in contact with the at least one fin structure. The first epitaxial material layer is separated from the at least one fin structure by the second epitaxial material layer. A gate structure present on the at least one fin structure.
    Type: Application
    Filed: May 1, 2014
    Publication date: November 5, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kangguo Cheng, Ramachandra Divakaruni, Ali Khakifirooz, Alexander Reznicek, Soon-Cheon Seo
  • Publication number: 20150249086
    Abstract: A third type of metal gate stack is provided above an isolation structure and between a replacement metal gate n-type field effect transistor and a replacement metal gate p-type field effect transistor. The third type of metal gate stack includes at least three different components. Notably, the third type of metal gate stack includes, as a first component, an n-type workfunction metal layer, as a second component, a p-type workfunction metal layer, and as a third component, a low resistance metal layer. In some embodiments, the uppermost surface of the first, second and third components of the third type of metal gate stack are all substantially coplanar with each other. In other embodiments, an uppermost surface of the third component of the third type of metal gate stack is non-substantially coplanar with an uppermost surface of both the first and second components of the third type of metal gate stack.
    Type: Application
    Filed: February 28, 2014
    Publication date: September 3, 2015
    Applicant: International Business Machines Corporation
    Inventors: Ramachandra Divakaruni, Sameer H. Jain, Viraj Y. Sardesai, Keith H. Tabakman
  • Publication number: 20150236024
    Abstract: Embodiments for the present invention provide a semiconductor device and methods for fabrication. In an embodiment of the present invention, a semiconductor structure comprises a first conductor horizontally formed on a semiconductor substrate. A second conductor is vertically formed in a semiconductor stack that includes the semiconductor substrate. An oxidized region is formed proximate to the first conductor. The second conductor is formed in a manner to be in electrical communication with the first conductor. The first conductor is formed in a manner to be laterally connected to the second conductor. The first conductor is formed in a manner to not traverse beneath the oxidized region. The first conductor is formed in a manner to have a reduced link-up resistance with adjacent epitaxial material included in the semiconductor structure.
    Type: Application
    Filed: February 20, 2014
    Publication date: August 20, 2015
    Applicant: International Business Machines Corporation
    Inventors: Emre Alptekin, Pooja R. Batra, Kangguo Cheng, Ramachandra Divakaruni, Johnathan E. Faltermeier, Reinaldo A. Vega