Patents by Inventor Anant Agarwal

Anant Agarwal 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: 20120280252
    Abstract: A semiconductor device includes a drift layer having a first conductivity type, a well region in the drift layer having a second conductivity type opposite the first conductivity type, and a source region in the well region, The source region has the first conductivity type and defines a channel region in the well region. The source region includes a lateral source region adjacent the channel region and a plurality of source contact regions extending away from the lateral source region opposite the channel region. A body contact region having the second conductivity type is between at least two of the plurality of source contact regions and is in contact with the well region. A source ohmic contact overlaps at least one of the source contact regions and the body contact region. A minimum dimension of a source contact area of the semiconductor device is defined by an area of overlap between the source ohmic contact and the at least one source contact region.
    Type: Application
    Filed: May 6, 2011
    Publication date: November 8, 2012
    Inventors: Sei-Hyung Ryu, Doyle Craig Capell, Lin Cheng, Sarit Dhar, Charlotte Jonas, Anant Agarwal, John Palmour
  • Publication number: 20120280270
    Abstract: A semiconductor device includes a drift layer having a first conductivity type, a well region in the drift layer having a second conductivity type opposite the first conductivity type, and a source region in the well region, The source region has the first conductivity type and defines a channel region in the well region. The source region includes a lateral source region adjacent the channel region and a plurality of source contact regions extending away from the lateral source region opposite the channel region. A body contact region having the second conductivity type is between at least two of the plurality of source contact regions and is in contact with the well region. A source ohmic contact overlaps at least one of the source contact regions and the body contact region. A minimum dimension of a source contact area of the semiconductor device is defined by an area of overlap between the source ohmic contact and the at least one source contact region.
    Type: Application
    Filed: May 16, 2011
    Publication date: November 8, 2012
    Inventors: Sei-Hyung Ryu, Doyle Craig Capell, Lin Cheng, Sarit Dhar, Charlotte Jonas, Anant Agarwal, John Palmour
  • Patent number: 8291400
    Abstract: A system comprises a plurality of computation units interconnected by an interconnection network. A method for configuring the system comprises receiving subsets of instructions corresponding to different portions of a program, each subset assigned to one of the computation units; scheduling instructions in a given subset for execution on the assigned computation unit, including scheduling communication instructions that send to or receive from a different computation unit over the interconnection network; allocating registers in a given computation unit for storing values accessed by instructions in a subset assigned to the given computation unit; and scheduling instructions after allocating registers to account for spills of values stored in allocated register to memory, preserving the order of communication instructions scheduled before allocating registers.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: October 16, 2012
    Assignee: Tilera Corporation
    Inventors: Walter Lee, Robert A. Gottlieb, Vineet Soni, Anant Agarwal, Richard Schooler
  • Publication number: 20120235164
    Abstract: A transistor structure optimizes current along the A-face of a silicon carbide body to form an AMOSFET that minimizes the JFET effect in the drift region during forward conduction in the on-state. The AMOSFET further shows high voltage blocking ability due to the addition of a highly doped well region that protects the gate corner region in a trench-gated device. The AMOSFET uses the A-face conduction along a trench sidewall in addition to a buried channel layer extending across portions of the semiconductor mesas defining the trench. A doped well extends from at least one of the mesas to a depth within the current spreading layer that is greater than the depth of the trench. A current spreading layer extends between the semiconductor mesas beneath the bottom of the trench to reduce junction resistance in the on-state. A buffer layer between the trench and the deep well further provides protection from field crowding at the trench corner.
    Type: Application
    Filed: May 29, 2012
    Publication date: September 20, 2012
    Applicant: CREE, INC.
    Inventors: Qingchun Zhang, Anant Agarwal, Charlotte Jonas
  • Publication number: 20120223330
    Abstract: Semiconductor devices having a high performance channel and method of fabrication thereof are disclosed. Preferably, the semiconductor devices are Metal-Oxide-Semiconductor (MOS) devices, and even more preferably the semiconductor devices are Silicon Carbide (SiC) MOS devices. In one embodiment, a semiconductor device includes a SiC substrate of a first conductivity type, a first well of a second conductivity type, a second well of the second conductivity type, and a surface diffused channel of the second conductivity type formed at the surface of semiconductor device between the first and second wells. A depth and doping concentration of the surface diffused channel are controlled to provide increased carrier mobility for the semiconductor device as compared to the same semiconductor device without the surface diffused channel region when in the on-state while retaining a turn-on, or threshold, voltage that provides normally-off behavior.
    Type: Application
    Filed: March 3, 2011
    Publication date: September 6, 2012
    Applicant: CREE, INC.
    Inventors: Sarit Dhar, Sei-Hyung Ryu, Lin Cheng, Anant Agarwal
  • Patent number: 8250555
    Abstract: A system comprises a plurality of computation units interconnected by an interconnection network.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: August 21, 2012
    Assignee: Tilera Corporation
    Inventors: Walter Lee, Robert A. Gottlieb, Vineet Soni, Anant Agarwal, Richard Schooler
  • Patent number: 8250507
    Abstract: A system comprises a plurality of computation units interconnected by an interconnection network. A method for configuring the system comprises accepting a set of instructions corresponding to a portion of a program that performs a computation repeatedly; identifying subsets of the instructions; and associating each subset with a different one of the computation units to form a specification of the set of instructions such that execution according to the specification forms a pipeline among at least some of the computation units.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: August 21, 2012
    Assignee: Massachusetts Institute of Technology
    Inventors: Anant Agarwal, Michelle Leger
  • Patent number: 8250556
    Abstract: A system comprises a plurality of computation units interconnected by an interconnection network. A method for configuring the system comprises receiving an initial partitioning of instructions into initial subsets corresponding to different portions of a program; forming a refined partitioning of the instructions into refined subsets each including one or more of the initial subsets, including determining whether to combine a first subset and a second subset to form a third subset according to a comparison of a communication cost between the first subset and second subset and a load cost of the third subset that is based at least in part on a number of instructions issued per cycle by a computation unit; and assigning each refined subset of instructions to one of the computation units for execution on the assigned computation unit.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: August 21, 2012
    Assignee: Tilera Corporation
    Inventors: Walter Lee, Robert A. Gottlieb, Vineet Soni, Anant Agarwal, Richard Schooler
  • Patent number: 8234451
    Abstract: A multicore processor comprises a plurality of cache memories, and a plurality of processor cores, each associated with one of the cache memories. Each of at least some of the cache memories is configured to maintain at least a portion of the cache memory in which each cache line is dynamically managed as either local to the associated processor core or shared among multiple processor cores.
    Type: Grant
    Filed: July 25, 2011
    Date of Patent: July 31, 2012
    Assignee: Tilera Corporation
    Inventors: Anant Agarwal, Ian R. Bratt, Matthew Mattina
  • Patent number: 8211770
    Abstract: A transistor structure optimizes current along the A-face of a silicon carbide body to form an AMOSFET that minimizes the JFET effect in the drift region during forward conduction in the on-state. The AMOSFET further shows high voltage blocking ability due to the addition of a highly doped well region that protects the gate corner region in a trench-gated device. The AMOSFET uses the A-face conduction along a trench sidewall in addition to a buried channel layer extending across portions of the semiconductor mesas defining the trench. A doped well extends from at least one of the mesas to a depth within the current spreading layer that is greater than the depth of the trench. A current spreading layer extends between the semiconductor mesas beneath the bottom of the trench to reduce junction resistance in the on-state. A buffer layer between the trench and the deep well further provides protection from field crowding at the trench corner.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: July 3, 2012
    Assignee: Cree, Inc.
    Inventors: Qingchun Zhang, Anant Agarwal, Charlotte Jonas
  • Patent number: 8200901
    Abstract: An apparatus comprises a plurality of processor cores, each comprising a computation unit and a memory. The apparatus further comprises an interconnection network to transmit data among the processor cores. At least some of the memories are configured as a cache for memory external to the processor cores, and at least some of the processor cores are configured to transmit a message over the interconnection network to access a cache of another processor core.
    Type: Grant
    Filed: January 3, 2011
    Date of Patent: June 12, 2012
    Assignee: Tilera Corporation
    Inventors: David Wentzlaff, Matthew Mattina, Anant Agarwal
  • Patent number: 8190855
    Abstract: An integrated circuit comprises a plurality of tiles. Each tile comprises a processor, and a switch including switching circuitry to forward data received over data paths from other tiles to the processor and to switches of other tiles, and to forward data received from the processor to switches of other tiles. The integrated circuit further comprises one or more interface modules including circuitry to transfer data to and from a device external to the tiles; and a sub-port routing network including circuitry to route data between a port of a switch and a plurality of sub-ports coupled to one or more interface modules.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: May 29, 2012
    Assignee: Tilera Corporation
    Inventors: Carl G. Ramey, David Wentzlaff, Anant Agarwal
  • Patent number: 8181168
    Abstract: A system comprises a plurality of computation units interconnected by an interconnection network. A method for configuring the system comprises forming subsets of instructions corresponding to different portions of a program, the subsets of instructions being related according to a control flow graph; forming one or more memory analysis regions that include one or more of the subsets of instructions, where each subset of instructions is included in a single memory analysis region; analyzing each memory analysis region to partition memory objects and instructions that access the memory objects into equivalence classes such that instructions within an equivalence class only access objects in the same equivalence class; and assigning memory access instructions a given equivalence class to one of the computation units for execution on the assigned computation unit.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: May 15, 2012
    Assignee: Tilera Corporation
    Inventors: Walter Lee, Robert A. Gottlieb, Vineet Soni, Anant Agarwal, Richard Schooler
  • Patent number: 8155113
    Abstract: An integrated circuit includes a plurality of tiles, and a plurality of interface modules coupled to the switches of a subset of the tiles. Each tile comprises a processor, and a switch including switching circuitry to forward data over data paths from other tiles to the processor and to switches of other tiles. At least some of the interface modules are configured to multiplex data from one or more parallel communication links of the switch to an multiplexed communication link having reduced parallelization, and mediate between a network protocol of the switch and a communication protocol of the multiplexed communication link.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: April 10, 2012
    Assignee: Massachusetts Institute of Technology
    Inventor: Anant Agarwal
  • Publication number: 20120068263
    Abstract: A semiconductor device includes a drift layer and a body region that forms a p-n junction with the drift layer. A contactor region is in the body region, and a shunt channel region extends through the body region from the contactor region to the drift layer. The shunt channel region has a length, thickness and doping concentration selected such that: 1) the shunt channel region is fully depleted when zero voltage is applied across the first and second terminals, 2) the shunt channel becomes conductive at a voltages less than the built-in potential of the drift layer to body region p-n junction, and/or 3) the shunt channel is not conductive for voltages that reverse bias the p-n junction between the drift region and the body region.
    Type: Application
    Filed: October 7, 2011
    Publication date: March 22, 2012
    Inventors: Allen Hefner, Sei-Hyung Ryu, Anant Agarwal
  • Patent number: 8127111
    Abstract: An integrated circuit comprises a plurality of tiles. Each tile comprises a processor including a storage module, wherein the processor is configured to process multiple streams of instructions, a switch including switching circuitry to forward data received over data paths from other tiles to the processor and to switches of other tiles, and to forward data received from the processor to switches of other tiles, and coupling circuitry configured to couple data resulting from processing an instruction from at least one of the streams of instructions to the storage module and to the switch.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: February 28, 2012
    Assignee: Tilera Corporation
    Inventors: David Wentzlaff, Anant Agarwal
  • Patent number: 8112581
    Abstract: A multicore processor comprises a plurality of cache memories; a plurality of processor cores, each associated with one of the cache memories; one or more memory interfaces providing memory access paths from the cache memories to a main memory; and one or more directory controllers for respective portions of the main memory, each associated with corresponding storage for directory state. Each corresponding storage provides space for maintaining directory state for each memory line that is indicated as stored in at least one of the cache memories such that the space for maintaining directory state is independent of the size of the main memory.
    Type: Grant
    Filed: December 2, 2010
    Date of Patent: February 7, 2012
    Assignee: Tilera Corporation
    Inventors: Anant Agarwal, Ian R. Bratt, Matthew Mattina
  • Publication number: 20120018738
    Abstract: Electronic device structures including semiconductor ledge layers for surface passivation and methods of manufacturing the same are disclosed. In one embodiment, the electronic device includes a number of semiconductor layers of a desired semiconductor material having alternating doping types. The semiconductor layers include a base layer of a first doping type that includes a highly doped well forming a first contact region of the electronic device and one or more contact layers of a second doping type on the base layer that have been etched to form a second contact region of the electronic device. The etching of the one or more contact layers causes substantial crystalline damage, and thus interface charge, on the surface of the base layer. In order to passivate the surface of the base layer, a semiconductor ledge layer of the semiconductor material is epitaxially grown on at least the surface of the base layer.
    Type: Application
    Filed: July 26, 2010
    Publication date: January 26, 2012
    Applicant: CREE, INC.
    Inventors: Qingchun Zhang, Anant Agarwal
  • Publication number: 20120018737
    Abstract: Electronic device structures that compensate for non-uniform etching on a semiconductor wafer and methods of fabricating the same are disclosed. In one embodiment, the electronic device includes a number of layers including a semiconductor base layer of a first doping type formed of a desired semiconductor material, a semiconductor buffer layer on the base layer that is also formed of the desired semiconductor material, and one or more contact layers of a second doping type on the buffer layer. The one or more contact layers are etched to form a second contact region of the electronic device. The buffer layer reduces damage to the semiconductor base layer during fabrication of the electronic device. Preferably, a thickness of the semiconductor buffer layer is selected to compensate for over-etching due to non-uniform etching on a semiconductor wafer on which the electronic device is fabricated.
    Type: Application
    Filed: July 21, 2010
    Publication date: January 26, 2012
    Applicant: Cree, Inc.
    Inventors: Qingchun Zhang, Anant Agarwal
  • Patent number: 8086554
    Abstract: Pattern matching in a plurality of interconnected processing engines includes: accepting a stream of input sequences over an interface and storing the input sequences; storing instructions for matching an input sequence to one or more patterns in memory accessible by a first set of one or more processing engines, and storing instructions for matching an input sequence to one or more patterns in memory accessible by a second set of one or more processing engines; distributing information identifying selected input sequences to the first and second sets of processing engines; and retrieving the identified input sequences to perform pattern matching in the first and second sets of processing engines.
    Type: Grant
    Filed: July 22, 2011
    Date of Patent: December 27, 2011
    Assignee: Tilera Corporation
    Inventors: Kenneth M. Steele, Anant Agarwal