Patents by Inventor David M. Rowell

David M. Rowell 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: 5948300
    Abstract: A semiconductor wafer furnace process tube includes one or more gas delivery lines which wind around the circumference of the process tube in a non-product region near one end to preheat the gas in the lines. The winding section begins within the non-product region of the heater and terminates prior to the location of the first wafer within the process tube. From the termination of the winding section, the delivery lines continue axially directly to the opposite end of the tube. The length of the lines within the winding section is preselected to adequately preheat the gas in the lines before the lines pass the wafers. In this manner, the gas is able to absorb energy from the non-product region of the furnace with minimal or no cooling of the wafers in the product region of the furnace. Additionally, the lines are routed to absorb energy equally around the circumference of the process tube and not create a cold side within the tube.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: September 7, 1999
    Assignee: Kokusai BTI Corporation
    Inventors: Lawrence R. Gero, David M. Rowell
  • Patent number: 5257926
    Abstract: A fast, safe pyrogenic external torch assembly that provides pure steam for semiconductor processing in semiconductor processing furnaces includes a gas injection nozzle subassembly, a pulse heater subassembly and a compressed-air-cooled heat-exchanging jacket subassembly. The gas injection nozzle subassembly includes plural oxygen gas injection nozzles and a hydrogen gas injection nozzle that cooperate to provide a torch that is well-behaved over the practicable range of oxygen and hydrogen gas supply rates and ratios, that may be quickly ramped to any desired gas flow conditions and that is free from the possibility of unwanted explosion due to incomplete hydrogen gas consumption. The pulse heater subassembly includes one or more blackbodies and a radiant energy source that are cooperative to quickly and efficiently provide one or more hot spots at the industry safe-ignition temperature.
    Type: Grant
    Filed: December 17, 1991
    Date of Patent: November 2, 1993
    Inventors: Gideon Drimer, Arie Glaser, David M. Rowell
  • Patent number: 4987033
    Abstract: Impact resistant clad composite armor and method for forming such armor. The impact resistant clad composite armor includes a ceramic core, and a layer of metal surrounding the ceramic material and bonded to the ceramic core. The metal layer is formed by cold isostatically pressing powder metal surrounding the ceramic core to a high initial density followed by vacuum sintering. The composite armor may be hot isostatically pressed to densify the powder metal to approximately 99% full density.
    Type: Grant
    Filed: December 20, 1988
    Date of Patent: January 22, 1991
    Assignee: Dynamet Technology, Inc.
    Inventors: Stanley Abkowitz, David M. Rowell, Harold L. Heussi, Harold P. Ludwig, Stephen A. Kraus
  • Patent number: 4968348
    Abstract: A titanium-based metal matrix microcomposite material. About 1% to about 25% by weight TiB.sub.2 is substantially uniformly incorporated in a titanium-based alloy matrix. The microcomposite material is formed by sintering at a temperature selected to preclude diffusion of TiB.sub.2 into the matrix. The microcomposite material may be used in a process for cladding a macrocomposite structure.
    Type: Grant
    Filed: November 28, 1989
    Date of Patent: November 6, 1990
    Assignee: Dynamet Technology, Inc.
    Inventors: Stanley Abkowitz, Harold L. Heussi, Harold P. Ludwig, David M. Rowell, Stephen A. Kraus
  • Patent number: 4906430
    Abstract: A titanium-based metal matrix microcomposite material. About 1% to about 25% by weight TiB.sub.2 is substantially uniformly incorporated in a titanium-based alloy matrix. The microcomposite material is formed by sintering at a temperature selected to preclude diffusion of TiB.sub.2 into the matrix. The microcomposite material may be used in a process for cladding a macrocomposite structure.
    Type: Grant
    Filed: July 29, 1988
    Date of Patent: March 6, 1990
    Assignee: Dynamet Technology Inc.
    Inventors: Stanley Abkowitz, Harold L. Heussi, Harold P. Ludwig, David M. Rowell, Stephen A. Kraus