Patents Represented by Attorney Philip Summa
  • Patent number: 7682709
    Abstract: A method of preparing an n-type epitaxial layer of aluminum nitride conductively doped with germanium comprises directing a molecular beam of aluminum atoms onto the growth surface of a substrate that provides an acceptable lattice match for aluminum nitride; directing a molecular beam of activated nitrogen to the growth surface of the substrate; and directing a molecular beam of germanium to the growth surface of the substrate; while maintaining the growth surface of the substrate at a temperature high enough to provide the surface mobility and sticking coefficient required for epitaxial growth, but lower than the temperature at which the surface would decompose or the epitaxial layer disassociate back into atomic or molecular species.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: March 23, 2010
    Assignee: North Carolina State University
    Inventors: Robert F. Davis, Cheng Wang
  • Patent number: 6272431
    Abstract: An apparatus and method for displaying a virtual map image slightly above the line of sight of a driver of a vehicle. The apparatus and method provide the virtual map image that is in a reflective relationship with the surrounding terrain thereby providing a map that is continuously in the same general azimuthal relationship to the driver as is the surrounding terrain. The virtual map may be scaled or distorted to provide information to a driver concerning distant objects and locations that would not ordinarily be available on heads-up map of the surrounding terrain.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: August 7, 2001
    Inventors: Thomas Zamojdo, Christopher Thomas Grabowski
  • Patent number: 6268570
    Abstract: The invention is a method of measuring an apparent weight of a substance, while concurrently measuring a surface temperature of the substance and an ambient air temperature surrounding the substance, then predicting buoyancy forces acting upon the substance based on these temperature measurements. Thereafter, the true weight of the substance can be determined by correcting the apparent weight by the predicted buoyancy forces acting upon the substance.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: July 31, 2001
    Assignee: CEM Corporation
    Inventors: Byron E. McLendon, Edward Earl King
  • Patent number: 6261154
    Abstract: An apparatus and associated method are disclosed for finishing the surfaces of workpieces, and that is particularly suitable for metal workpieces. The apparatus includes a tub, finishing media in the tub, means for moving the media in the tub in a generally revolving motion in the tub, and means for positioning and rotating a workpiece to be polished in the media about an axis that is oblique to the axis about which the media revolves and without moving the position of the workpiece with respect to the tub as the workpiece rotates.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: July 17, 2001
    Inventor: Jeffrey William McEneny
  • Patent number: 6250060
    Abstract: A high efficiency method of producing a high quality knit fabricis diclosed. The method includes the steps of drafting a blended sliver of cotton fibers and polyester fibers in a four roll draffing zone in which the nip to nip spacing in the break zone is no more than 2.5 mm longer than the effective fiber length of the polyester fibers, and no more than 1.5 mm greater than the effective fiber length in the intermediate zone, and at least 7 mm greater than the effective fiber length in the front zone, thereafter spinning the drafted sliver into yarn at a take up speed of greater than 150 meters per minute, and thereafter knitting the spun yarn into fabric.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: June 26, 2001
    Assignee: Wellman, Inc.
    Inventors: Todd Joseph Scheerer, Winston Patrick Moore
  • Patent number: 6246038
    Abstract: A microwave vessel system for external and noninvasive pressure monitoring and control is disclosed. The system comprises a reaction vessel formed of a material that is transparent to microwave radiation, with the reaction vessel including a portion that is movable under pressure generated by a chemical reaction inside the vessel while maintaining the reaction sealed inside the vessel. A sensor is adjacent to the movable portion of the vessel for detecting the motion of the movable portion as the portion responds to pressure generated inside the vessel. The system includes means for maintaining the sensor against the movable portion while microwaves are applied to the vessel so that the movement of the movable portion under pressure is detected by the sensor.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: June 12, 2001
    Assignee: CEM Limited, LLC
    Inventors: James Edward Thomas, Wyatt Price Hargett, Jr., Edward Earl King
  • Patent number: 6246076
    Abstract: A dielectric structure is disclosed for silicon carbide-based semiconductor devices. In gated devices, the structure includes a layer of silicon carbide, a layer of silicon dioxide on the silicon carbide layer, a layer of another insulating material on the silicon dioxide layer, with the insulating material having a dielectric constant higher than the dielectric constant of silicon dioxide, and a gate contact to the insulating material. In other devices the dielectric structure forms an enhanced passivation layer or field insulator.
    Type: Grant
    Filed: August 28, 1998
    Date of Patent: June 12, 2001
    Assignee: Cree, Inc.
    Inventors: Lori A. Lipkin, John Williams Palmour
  • Patent number: 6227041
    Abstract: A method and associated apparatus are disclosed for measuring volatile content of samples that are particularly suitable for samples that tend to bum when heated. The method includes the steps of applying microwave radiation at a predetermined power level to a moisture-containing sample to drive volatiles from the sample, monitoring the weight of the sample during the application of microwave power, monitoring the temperature of the sample during the application of microwave power without contacting either the sample or anything in contact with the sample, and moderating the microwave power being applied to the sample based upon the monitored temperature to maintain the temperature of the sample at or below a pre-determined set point temperature below which the sample will not bum.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: May 8, 2001
    Assignee: CEM Corporation
    Inventors: Michael J. Collins, William Edward Jennings
  • Patent number: 6221488
    Abstract: A method is disclosed of producing a blended fabric of polyester and cotton with superior low pilling characteristics. The method comprises polymerizing a melt consisting essentially of terephthalic acid, ethylene glycol and at least about 1300 parts per million of pentaerythritol to an intrinsic viscosity of at least about 0.55 dl/g. The resulting polymer can be spun into filament, textured, cut into staple, spun into yarn, and formed into fabric. The method and resulting polyester also have advantages in the production of polyester bottle resin and the resulting bottles.
    Type: Grant
    Filed: July 27, 2000
    Date of Patent: April 24, 2001
    Assignee: Wellman, Inc.
    Inventors: Billy Mack Humelsine, Carl S. Nichols
  • Patent number: 6217662
    Abstract: A susceptor is disclosed for minimizing or eliminating thermal gradients that affect a substrate wafer during epitaxial growth. The susceptor comprises a first susceptor portion including a surface for receiving a semiconductor substrate wafer thereon, and a second susceptor portion facing the substrate-receiving surface and spaced from the substrate-receiving surface. The spacing is sufficiently large to permit the flow of gases therebetween for epitaxial growth on a substrate on the surface, while small enough for the second susceptor portion to heat the exposed face of a substrate to substantially the same temperature as the first susceptor portion heats the face of a substrate that is in direct contact with the substrate-receiving surface.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: April 17, 2001
    Assignee: Cree, Inc.
    Inventors: Hua-Shuang Kong, Calvin Carter, Jr., Joseph Sumakeris
  • Patent number: 6218680
    Abstract: A semi-insulating bulk single crystal of silicon carbide is disclosed that has a resistivity of at least 5000 &OHgr;-cm at room temperature and a concentration of deep level trapping elements that is below the amounts that will affect the resistivity of the crystal, preferably below detectable levels. A method of forming the crystal is also disclosed, along with some resulting devices that take advantage of the microwave frequency capabilities of devices formed using substrates according to the invention.
    Type: Grant
    Filed: May 18, 1999
    Date of Patent: April 17, 2001
    Assignee: Cree, Inc.
    Inventors: Calvin H. Carter, Jr., Mark Brady, Valeri F. Tsvetkov
  • Patent number: 6218007
    Abstract: A method is disclosed for spinning polyester staple to produce dark dyeing yarns as compared to yarns having an otherwise similar composition. The method includes spinning polyester staple into yarn, in which the polyester includes between about 0.5 and 4 percent by weight of polyethylene glycol, into yarn in a rotor spinning machine at a rotor speed of between about 110,000 and 120,000 rpm and at a tension of between about 2.5 and 3.2 grams/tex. A resulting polyester fiber is also disclosed of between about 1.2 and 2.25 denier per filament, and that contains between about 0.5 and 4 percent by weight of polyethylene glycol, and with a fiber tenacity of 4.7 grams per denier or less.
    Type: Grant
    Filed: May 18, 1999
    Date of Patent: April 17, 2001
    Assignee: Wellman, Inc.
    Inventors: David Michael Russell, Winston Patrick Moore, Robert Alton Usher, Jr.
  • Patent number: 6214270
    Abstract: Disclosed is a method of copolymerizing polyethylene glycol (PEG) into polyethylene terephthalate (PET) to achieve a polyethylene glycol-modified polyester composition that can be spun into filaments. The method includes the steps of copolymerizing polyethylene glycol into polyethylene terephthalate in the melt phase to form a copolyester composition, then polymerizing the copolyester composition in the solid phase until the copolyester is capable of achieving a melt viscosity that facilitates the spinning of filaments, and thereafter spinning filaments from the copolyester. A copolyester composition comprised of polyethylene glycol and polyethylene terephthalate is also disclosed. Fabrics made from fibers formed from the copolyester composition possess wetting, wicking, drying, flame-retardancy, static-dissipation, and soft hand properties that are superior to those of fabrics formed from conventional polyethylene terephthalate fibers of the same yarn and fabric construction.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: April 10, 2001
    Assignee: Wellman, Inc.
    Inventor: James Burch Branum
  • Patent number: 6207462
    Abstract: A method and apparatus are disclosed for analyzing the aggregate content of asphalt-aggregate compositions. The method includes placing a preheated, preweighed container carrying a sample of an asphalt-aggregate composition into a preheated furnace with the preheated furnace being warmer than the preheated sample, continuing to heat the furnace while drawing air through the furnace at a rate that avoids impeding the heating of the furnace or the sample until the sample in the container reaches its combustion temperature and the combustion of the sample becomes exothermic, initiating a second draw of air around rather than through the furnace to moderate the exterior temperature of the furnace, accelerating the draw through the furnace to increase the rate of combustion of the exothermic reaction, and reweighing the container and sample after combustion is complete.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: March 27, 2001
    Assignee: CEM Corporation
    Inventors: David Allan Barclay, Ali Regimand
  • Patent number: 6200917
    Abstract: Large single crystals of silicon carbide are grown in a furnace sublimation system. The crystals are grown with compensating levels of p-type and n-type dopants (i.e., roughly equal levels of the two dopants) in order to produce a crystal that is essentially colorless. The crystal may be cut and fashioned into synthetic gemstones having extraordinary toughness and hardness, and a brilliance meeting or exceeding that of diamond.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: March 13, 2001
    Assignee: Cree, Inc.
    Inventors: Calvin H. Carter, Valeri F. Tsvetkov, Robert C. Glass
  • Patent number: 6201262
    Abstract: An optoelectronic device with a Group III Nitride active layer is disclosed that comprises a silicon carbide substrate; an optoelectronic diode with a Group III nitride active layer; a buffer structure selected from the group consisting of gallium nitride and indium gallium nitride between the silicon carbide substrate and the optoelectronic diode; and a stress-absorbing structure comprising a plurality of predetermined stress-relieving areas within the crystal structure of the buffer structure, so that stress-induced cracking that occurs in the buffer structure occurs at predetermined areas rather than elsewhere in the buffer structure.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: March 13, 2001
    Assignee: Cree, Inc.
    Inventors: John Adam Edmond, Hua-Shuang Kong, Kathleen Marie Doverspike, Michelle Turner Leonard
  • Patent number: 6190917
    Abstract: A method and apparatus are disclosed for analyzing asphalt-aggregate compositions. The method includes directing sufficient microwave radiation from a microwave source to a sample of an asphalt-aggregate composition to ignite the asphalt in the composition and to thereafter entirely combust the asphalt in the sample. The apparatus includes a source of microwave radiation, a cavity in communication with the microwave source, a sample holder in the cavity for holding a sample of an asphalt-aggregate composition during exposure to microwaves from the source, thermal insulation between the sample holder and the remainder of the cavity, and means for minimizing or eliminating any undesired combustion products generated by the burning asphalt.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: February 20, 2001
    Assignee: CEM Corporation
    Inventors: David Allan Barclay, Ali Regimand
  • Patent number: 6187606
    Abstract: An optoelectronic device with a Group III Nitride active layer is disclosed that comprises a silicon carbide substrate; an optoelectronic diode with a Group III nitride active layer; a buffer structure selected from the group consisting of gallium nitride and indium gallium nitride between the silicon carbide substrate and the optoelectronic diode; and a stress-absorbing structure comprising a plurality of predetermined stress-relieving areas within the crystal structure of the buffer structure, so that stress-induced cracking that occurs in the buffer structure occurs at predetermined areas rather than elsewhere in the buffer structure.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: February 13, 2001
    Assignee: Cree, Inc.
    Inventors: John Adam Edmond, Hua-Shuang Kong, Kathleen Marie Doverspike, Michelle Turner Leonard
  • Patent number: 6182685
    Abstract: An injector structure is disclosed for delivering liquid additives, and particularly colorants, into a polyester production system capable of being cleaned without removal from a production line. The device includes a valve body with an internal channel extending longitudinally therein, a hollow housing for receiving a reciprocating stem, and an insulating jacket for minimizing the affect that heat from a melt extruder may have on the liquid colorant as the liquid colorant flows through the injector. A fluid inlet in communication with the internal channel is provided for delivering fluid from an external source to the valve body. The reciprocating stem, in an open position, allows liquid colorant to flow from the fluid inlet through the internal channel and out of a discharge opening at one end of the valve body. In a closed position, the reciprocating stem blocks the internal channel thereby preventing delivery of the fluid from the fluid inlet to the discharge opening.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: February 6, 2001
    Assignee: Wellman, Inc.
    Inventors: Christopher Waddell Goff, Charles Melvin King
  • Patent number: 6180958
    Abstract: A silicon carbide insulated gate power transistor is disclosed that demonstrates increased maximum voltage. The transistor comprises a field effect or insulated gate transistor with a protective region adjacent the insulated gate that has the opposite conductivity type from the source for protecting the gate insulator material from the degrading or breakdown effects of a large voltage applied across the device.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: January 30, 2001
    Inventor: James Albert Cooper, Jr.