Patents by Inventor Dureseti Chidambarrao

Dureseti Chidambarrao 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: 20140103366
    Abstract: A semiconductor structure and method of manufacturing is provided. The method of manufacturing includes forming shallow trench isolation (STI) in a substrate and providing a first material and a second material on the substrate. The first material and the second material are mixed into the substrate by a thermal anneal process to form a first island and second island at an nFET region and a pFET region, respectively. A layer of different material is formed on the first island and the second island. The STI relaxes and facilitates the relaxation of the first island and the second island. The first material may be deposited or grown Ge material and the second material may deposited or grown Si:C or C. A strained Si layer is formed on at least one of the first island and the second island.
    Type: Application
    Filed: December 13, 2013
    Publication date: April 17, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Dureseti CHIDAMBARRAO, Omer H. DOKUMACI, Oleg GLUSCHENKOV
  • Publication number: 20140061583
    Abstract: A nanotubular MOSFET device extends a scaling roadmap while maintaining good short channel effects and providing competitive drive current. The nanotubular MOSFET device includes a concentric tubular inner and outer gate separated from each other by a tubular shaped epitaxially grown silicon layer, and a source and drain respectively separated by spacers surrounding the tubular inner and outer gates.
    Type: Application
    Filed: November 6, 2013
    Publication date: March 6, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Daniel Tekleab, Hung H. Tran, Jeffrey W. Sleight, Dureseti Chidambarrao
  • Patent number: 8642434
    Abstract: While embedded silicon germanium alloy and silicon carbon alloy provide many useful applications, especially for enhancing the mobility of MOSFETs through stress engineering, formation of alloyed silicide on these surfaces degrades device performance. The present invention provides structures and methods for providing unalloyed silicide on such silicon alloy surfaces placed on semiconductor substrates. This enables the formation of low resistance contacts for both mobility enhanced PFETs with embedded SiGe and mobility enhanced NFETs with embedded Si:C on the same semiconductor substrate. Furthermore, this invention provides methods for thick epitaxial silicon alloy, especially thick epitaxial Si:C alloy, above the level of the gate dielectric to increase the stress on the channel on the transistor devices.
    Type: Grant
    Filed: February 16, 2012
    Date of Patent: February 4, 2014
    Assignee: International Business Machines Corporation
    Inventors: Yaocheng Liu, Dureseti Chidambarrao, Oleg Gluschenkov, Judson R. Holt, Renee T. Mo, Kern Rim
  • Patent number: 8629501
    Abstract: A stack pad layers including a first pad oxide layer, a pad nitride layer, and a second pad oxide layer are formed on a semiconductor-on-insulator (SOI) substrate. A deep trench extending below a top surface or a bottom surface of a buried insulator layer of the SOI substrate and enclosing at least one top semiconductor region is formed by lithographic methods and etching. A stress-generating insulator material is deposited in the deep trench and recessed below a top surface of the SOI substrate to form a stress-generating buried insulator plug in the deep trench. A silicon oxide material is deposited in the deep trench, planarized, and recessed. The stack of pad layer is removed to expose substantially coplanar top surfaces of the top semiconductor layer and of silicon oxide plugs. The stress-generating buried insulator plug encloses, and generates a stress to, the at least one top semiconductor region.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: January 14, 2014
    Assignee: International Business Machines Corporation
    Inventors: Huilong Zhu, Brian J. Greene, Dureseti Chidambarrao, Gregory G. Freeman
  • Patent number: 8629022
    Abstract: A method of forming a semiconductor structure is provided. The method includes providing a structure including at least one dummy gate region located on a surface of a semiconductor substrate and a dielectric material layer located on sidewalls of the at least one dummy gate region. Next, a portion of the dummy gate region is removed exposing an underlying high k gate dielectric. A sloped threshold voltage adjusting material layer is then formed on an upper surface of the high k gate dielectric, and thereafter a gate conductor is formed atop the sloped threshold voltage adjusting material layer.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: January 14, 2014
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Sunfei Fang, Yue Liang, Xiaojun Yu, Jun Yuan
  • Publication number: 20130320340
    Abstract: A physical test integrated circuit has a plurality of repeating circuit portions corresponding to an integrated circuit design. A first of the portions is fabricated with a nominal block mask location, and additional ones of the portions are deliberately fabricated with predetermined progressive increased offset of the block mask location from the nominal block mask location. For each of the portions, the difference in threshold voltage between a first field effect transistor and a second field effect transistor is determined. The predetermined progressive increased offset of the block mask location is in a direction from the first field effect transistor to the second field effect transistor. The block mask overlay tolerance is determined at a value of the progressive increased offset corresponding to an inflection of the difference in threshold voltage from a zero difference. A method for on-chip monitoring, and corresponding circuits, are also disclosed.
    Type: Application
    Filed: June 5, 2012
    Publication date: December 5, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Emrah Acar, Aditya Bansal, Dureseti Chidambarrao, Liang-Teck Pang, Amith Singhee
  • Publication number: 20130288440
    Abstract: A semiconductor structure and method for forming dielectric spacers and epitaxial layers for a complementary metal-oxide-semiconductor field effect transistor (CMOS transistor) are disclosed. Specifically, the structure and method involves forming dielectric spacers that are disposed in trenches and are adjacent to the silicon substrate, which minimizes leakage current. Furthermore, epitaxial layers are deposited to form source and drain regions, wherein the source region and drain regions are spaced at a distance from each other. The epitaxial layers are disposed adjacent to the dielectric spacers and the transistor body regions (i.e., portion of substrate below the gates), which can minimize transistor junction capacitance. Minimizing transistor junction capacitance can enhance the switching speed of the CMOS transistor.
    Type: Application
    Filed: June 21, 2013
    Publication date: October 31, 2013
    Inventors: Dureseti Chidambarrao, Ramachandran Muralidhar, Philip J. Oldiges, Viorel Ontalus
  • Publication number: 20130273699
    Abstract: A delta doping of silicon by carbon is provided on silicon surfaces by depositing a silicon carbon alloy layer on silicon surfaces, which can be horizontal surfaces of a bulk silicon substrate, horizontal surfaces of a top silicon layer of a semiconductor-on-insulator substrate, or vertical surfaces of silicon fins. A p-type field effect transistor (PFET) region and an n-type field effect transistor (NFET) region can be differentiated by selectively depositing a silicon germanium alloy layer in the PFET region, and not in the NFET region. The silicon germanium alloy layer in the PFET region can overlie or underlie a silicon carbon alloy layer. A common material stack can be employed for gate dielectrics and gate electrodes for a PFET and an NFET. Each channel of the PFET and the NFET includes a silicon carbon alloy layer, and is differentiated by the presence or absence of a silicon germanium layer.
    Type: Application
    Filed: June 13, 2013
    Publication date: October 17, 2013
    Inventors: Dureseti Chidambarrao, Brian J. Greene, Yue Liang, Xiaojun Yu
  • Patent number: 8541814
    Abstract: A semiconductor structure and method for forming dielectric spacers and epitaxial layers for a complementary metal-oxide-semiconductor field effect transistor (CMOS transistor) are disclosed. Specifically, the structure and method involves forming dielectric spacers that are disposed in trenches and are adjacent to the silicon substrate, which minimizes leakage current. Furthermore, epitaxial layers are deposited to form source and drain regions, wherein the source region and drain regions are spaced at a distance from each other. The epitaxial layers are disposed adjacent to the dielectric spacers and the transistor body regions (i.e., portion of substrate below the gates), which can minimize transistor junction capacitance. Minimizing transistor junction capacitance can enhance the switching speed of the CMOS transistor.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: September 24, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Ramachandran Muralidhar, Philip J Oldiges, Viorel Ontalus
  • Publication number: 20130238263
    Abstract: Impact on parametric performance of physical design choices for transistors is scored for on-current and off-current of the transistors. The impact of the design parameters are incorporated into parameters that measure predicted shift in mean on-current and mean off-current and parameters that measure predicted increase in deviations in the distribution of on-current and the off-current. Statistics may be taken at a cell level, a block level, or a chip level to optimize a chip design in a design phase, or to predict changes in parametric yield during manufacturing or after a depressed parametric yield is observed. Further, parametric yield and current level may be predicted region by region and compared with observed thermal emission to pinpoint any anomaly region in a chip to facilitate detection and correction in any mistakes in chip design.
    Type: Application
    Filed: April 22, 2013
    Publication date: September 12, 2013
    Applicant: Mentor Graphics Corporation
    Inventors: James A. Culp, Paul Chang, Dureseti Chidambarrao, Praveen Elakkumanan, Jason Hibbeler, Anda C. Mocuta
  • Patent number: 8492268
    Abstract: An IC including first metal layer having wiring running in a first direction; a second metal layer having wiring running in a second direction perpendicular to the first direction; and a first via layer between the first metal layer and the second metal layer, the first via layer including a viabar interconnecting the first metal layer to the second metal layer at a first location where the first metal layer vertically coincides with the second metal layer and, at a second location, connecting to wiring of the first metal layer but not wiring of the second metal layer.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: July 23, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Stephen E. Greco, Kia S. Low
  • Patent number: 8492802
    Abstract: An electronic device includes a conductive channel defining a crystal structure and having a length and a thickness tC; and a dielectric film of thickness tg in contact with a surface of the channel. Further, the film comprises a material that exerts one of a compressive or a tensile force on the contacted surface of the channel such that electrical mobility of the charge carriers (electrons or holes) along the channel length is increased due to the compressive or tensile force in dependence on alignment of the channel length relative to the crystal structure. Embodiments are given for chips with both hole and electron mobility increased in different transistors, and a method for making such a transistor or chip.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: July 23, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Xiao Hu Liu, Lidija Sekaric
  • Publication number: 20130168695
    Abstract: A delta doping of silicon by carbon is provided on silicon surfaces by depositing a silicon carbon alloy layer on silicon surfaces, which can be horizontal surfaces of a bulk silicon substrate, horizontal surfaces of a top silicon layer of a semiconductor-on-insulator substrate, or vertical surfaces of silicon fins. A p-type field effect transistor (PFET) region and an n-type field effect transistor (NFET) region can be differentiated by selectively depositing a silicon germanium alloy layer in the PFET region, and not in the NFET region. The silicon germanium alloy layer in the PFET region can overlie or underlie a silicon carbon alloy layer. A common material stack can be employed for gate dielectrics and gate electrodes for a PFET and an NFET. Each channel of the PFET and the NFET includes a silicon carbon alloy layer, and is differentiated by the presence or absence of a silicon germanium layer.
    Type: Application
    Filed: January 4, 2012
    Publication date: July 4, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Dureseti Chidambarrao, Brian J. Greene, Yue Liang, Xiaojun Yu
  • Publication number: 20130168776
    Abstract: A complementary metal oxide semiconductor (CMOS) device including a substrate including a first active region and a second active region, wherein each of the first active region and second active region of the substrate are separated by from one another by an isolation region. A n-type semiconductor device is present on the first active region of the substrate, in which the n-type semiconductor device includes a first portion of a gate structure. A p-type semiconductor device is present on the second active region of the substrate, in which the p-type semiconductor device includes a second portion of the gate structure. A connecting gate portion provides electrical connectivity between the first portion of the gate structure and the second portion of the gate structure. Electrical contact to the connecting gate portion is over the isolation region, and is not over the first active region and/or the second active region.
    Type: Application
    Filed: January 3, 2012
    Publication date: July 4, 2013
    Applicant: International Business Machines Corporation
    Inventors: Yue Liang, Dureseti Chidambarrao, Brian J. Greene, William K. Henson, Unoh Kwon, Shreesh Narasimha, Xiaojun Yu
  • Patent number: 8476706
    Abstract: A delta doping of silicon by carbon is provided on silicon surfaces by depositing a silicon carbon alloy layer on silicon surfaces, which can be horizontal surfaces of a bulk silicon substrate, horizontal surfaces of a top silicon layer of a semiconductor-on-insulator substrate, or vertical surfaces of silicon fins. A p-type field effect transistor (PFET) region and an n-type field effect transistor (NFET) region can be differentiated by selectively depositing a silicon germanium alloy layer in the PFET region, and not in the NFET region. The silicon germanium alloy layer in the PFET region can overlie or underlie a silicon carbon alloy layer. A common material stack can be employed for gate dielectrics and gate electrodes for a PFET and an NFET. Each channel of the PFET and the NFET includes a silicon carbon alloy layer, and is differentiated by the presence or absence of a silicon germanium layer.
    Type: Grant
    Filed: January 4, 2012
    Date of Patent: July 2, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Brian J. Greene, Yue Liang, Xiaojun Yu
  • Patent number: 8466496
    Abstract: A complementary metal oxide semiconductor (CMOS) device that may include a substrate having a first active region and a second active region that are separated from one another by an isolation region. An n-type semiconductor device is present on the first active region that includes a first gate structure having a first gate dielectric layer and an n-type work function metal layer, wherein the n-type work function layer does not extend onto the isolation region. A p-type semiconductor device is present on the second active region that includes a second gate structure having a second gate dielectric layer and a p-type work function metal layer, wherein the p-type work function layer does not extend onto the isolation region. A connecting gate structure extends across the isolation region into direct contact with the first gate structure and the second gate structure.
    Type: Grant
    Filed: November 17, 2011
    Date of Patent: June 18, 2013
    Assignee: International Business Machines Corporation
    Inventors: Xiaojun Yu, Dureseti Chidambarrao, Brian J. Greene, Yue Liang
  • Patent number: 8453100
    Abstract: A method (and computer program) identify shapes and locations of transistor elements within a geometric circuit layout. The transistor elements include an active area, at least one gate conductor and other transistor elements. Also, the gate conductor has sides running in a first direction, and has a width dimension running in a second direction perpendicular to the first direction. The method defines regions within the geometric circuit layout. To do so, the method defines a first region having a perimeter positioned along the sides of the gate conductor where the gate conductor intersects the active area and then expands the perimeter of the first region in the second direction to edges of the active area to define a perimeter of a second region. The first region and the second share perimeters in the first direction. The method then expands the perimeter of the second region in the first direction to define a perimeter of a third region.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: May 28, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Richard Q. Williams
  • Publication number: 20130126976
    Abstract: A complementary metal oxide semiconductor (CMOS) device that may include a substrate having a first active region and a second active region that are separated from one another by an isolation region. An n-type semiconductor device is present on the first active region that includes a first gate structure having a first gate dielectric layer and an n-type work function metal layer, wherein the n-type work function layer does not extend onto the isolation region. A p-type semiconductor device is present on the second active region that includes a second gate structure having a second gate dielectric layer and a p-type work function metal layer, wherein the p-type work function layer does not extend onto the isolation region. A connecting gate structure extends across the isolation region into direct contact with the first gate structure and the second gate structure.
    Type: Application
    Filed: November 17, 2011
    Publication date: May 23, 2013
    Applicant: International Business Machines Corporation
    Inventors: Xiaojun Yu, Dureseti Chidambarrao, Brian J. Greene, Yue Liang
  • Patent number: 8445974
    Abstract: A semiconductor structure is provided that includes at least one asymmetric gate stack located on a surface of a semiconductor structure. The at least one asymmetric gate stack includes, from bottom to top, a high k gate dielectric, a sloped threshold voltage adjusting material layer and a gate conductor. A method of forming such a semiconductor structure is also provided in which a line of sight deposition process is used in forming the sloped threshold voltage adjusting material layer in which the deposition is tilted within respect to a horizontal surface of a semiconductor structure.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: May 21, 2013
    Assignee: International Business Machines Corporation
    Inventors: Dureseti Chidambarrao, Sunfei Fang, Yue Liang, Xiaojun Yu, Jun Yuan
  • Patent number: 8429576
    Abstract: Impact on parametric performance of physical design choices for transistors is scored for on-current and off-current of the transistors. The impact of the design parameters are incorporated into parameters that measure predicted shift in mean on-current and mean off-current and parameters that measure predicted increase in deviations in the distribution of on-current and the off-current. Statistics may be taken at a cell level, a block level, or a chip level to optimize a chip design in a design phase, or to predict changes in parametric yield during manufacturing or after a depressed parametric yield is observed. Further, parametric yield and current level may be predicted region by region and compared with observed thermal emission to pinpoint any anomaly region in a chip to facilitate detection and correction in any mistakes in chip design.
    Type: Grant
    Filed: May 15, 2012
    Date of Patent: April 23, 2013
    Assignee: Mentor Graphics Corporation
    Inventors: James A. Culp, Paul Chang, Dureseti Chidambarrao, Praveen Elakkumanan, Jason Hibbeler, Anda C. Mocuta