Patents by Inventor Timothy T. Zielinski

Timothy T. Zielinski 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: 5702532
    Abstract: Multiple solid precursor bubblers are used to alleviate channeling effects caused by high carrying gas flow rates to provide for deposition of indium-based epitaxial materials in high-capacity MOCVD reactor systems. Precracking of precursor materials that exhibit higher dissociation temperatures using heated manifolds or heated susceptor, and rotation of individual wafers in a multi-wafer reactor chamber enhance thickness uniformity, surface morphology and electronic properties of deposited epitaxial layers.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: December 30, 1997
    Assignee: Hughes Aircraft Company
    Inventors: Cheng P. Wen, Randy K. Rolph, Timothy T. Zielinski
  • Patent number: 5553395
    Abstract: A cone-shaped bubbler for use with solid metal organic source material used in metal organic chemical vapor phase deposition systems, and a method of producing carrying gas saturated with source material that is injected into such systems. The bubbler comprises a sealed container having a slanted wall with an inverted cone-shaped cross section. Solid metal organic source material is disposed in the container. A heat bath surrounds the sealed container. A carrying gas inlet is disposed adjacent the top of the container. Carrying gas is injected in a tangential direction relative to the source material, and a whirlpool effect is generated by the tangential gas flow that imparts a centrifugal force to gas molecules, pushing the source material against the wall to promote heat flow from the heat bath to sustain high rate sublimation. A gas outlet is disposed adjacent the bottom of the container.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: September 10, 1996
    Assignee: Hughes Aircraft Company
    Inventors: Cheng P. Wen, Randy K. Rolph, Timothy T. Zielinski
  • Patent number: 4407694
    Abstract: Silicon doping of GaAs epitaxial layers grown using the AsCl.sub.3 /H.sub.2 /GaAs:Ga CVD system is accomplished using AsCl.sub.3 :SiCl.sub.4 liquid doping solutions. These solutions can be readily prepared with reproducible compositions and provide excellent doping control. Fine adjustments in the doping level can be achieved by adjusting the H.sub.2 flow rate and by varying the temperature of the doping solution. Doping levels may range from about 5.times.10.sup.15 to 5.times.10.sup.19 cm.sup.-3 by adjusting the mole fraction of SiCl.sub.4 in the doping solution and the H.sub.2 flow rate to change the mole fraction of P.sub.HCl. The epitaxial layers doped using this technique have excellent room temperature and liquid nitrogen mobilities for electron concentrations between 1.times.10.sup.16 cm.sup.-3 and 8.times.10.sup.18 cm.sup.-3. This doping method is particularly useful for the growth of GaAs epitaxial layers for FET devices.
    Type: Grant
    Filed: June 22, 1981
    Date of Patent: October 4, 1983
    Assignee: Hughes Aircraft Company
    Inventors: Victor K. Eu, Milton Feng, Timothy T. Zielinski, James M. Whelan