Patents by Inventor Walter Precht

Walter Precht 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: 5190890
    Abstract: A semiconductor wafer base is disclosed which is suitable for fabrication of devices in silicon carbide, comprising a single crystal substrate which is a transition metal carbide alloy having cubic crystal structure and an unpolytyped, single crystal 3C-silicon carbide overlay epitaxially related to the substrate. Preferably, the substrate is an alloy of two or more of titanium carbide, tantalum carbide, vanadium carbide, and niobium carbide, with lattice parameter differing from 3C-silicon carbide by less than about 1%. Use of the transition metal carbide alloys enables the preparation of large, single crystal substrates free from cracks, dislocations, or other defects, suitable for epitaxial deposition of 3C-silicon carbide. The 3C-silicon carbide epitaxial overlay may be deposited by any suitable technique, including chemical vapor deposition and reactive evaporation, and may be doped with n- or p-type dopants.
    Type: Grant
    Filed: August 8, 1991
    Date of Patent: March 2, 1993
    Assignee: Advanced Technology Materials, Inc.
    Inventors: Walter Precht, Richard Koba, Donald Kupp, Delwyn Cummings
  • Patent number: 5043773
    Abstract: A semiconductor wafer base is disclosed which is suitable for fabrication of devices in silicon carbide, comprising a single crystal substrate which is a transition metal carbide alloy having cubic crystal structure and an unpolytyped, single crystal 3C-silicon carbide overlay epitaxially related to the substrate. Preferably, the substrate is an alloy of two or more of titanium carbide, tantalum carbide, vanadium carbide, and niobium carbide, with alttice parameter differing from 3C-silicon carbide by less than about 1%. Use of the transition metal carbide alloys enables the preparation of large, single crystal substrates free from cracks, dislocations, or other defects, suitable for epitaxial deposition of 3C-silicon carbide. The 3C-silicon carbide epitaxial overlay may be deposited by any suitable technique, including chemical vapor deposition and reactive evaporation, and may be doped with n- or p-type dopants.
    Type: Grant
    Filed: June 4, 1990
    Date of Patent: August 27, 1991
    Assignee: Advanced Technology Materials, Inc.
    Inventors: Walter Precht, Richard Koba, Donald Kupp, Delwyn Cummings
  • Patent number: 4865666
    Abstract: Intermetallics capable of use as structural elements, exhibiting relatively high ductility and low brittleness, comprise ternary and quaternary TiAl.sub.3 alloys of the general formulae Al--Ti--M and Al--Ti--M--M', wherein M is selected from Cu, Ni, and Fe, M' is selected from V, Nb, and Ta. Such materials exhibit cubic, Ll.sub.2 crystal structures.
    Type: Grant
    Filed: October 14, 1987
    Date of Patent: September 12, 1989
    Assignee: Martin Marietta Corporation
    Inventors: K. Sharvan Kumar, Walter Precht
  • Patent number: 3945863
    Abstract: A process for pretreating metal powders for the preparation of dispersion hardened metal alloys whereby an iron, cobalt or nickel base metal powder is homogeneously mixed with a chromium powder and with a prealloyed metal carbide powder and granulated to a powder granulate. The granulate is then classified and reduced to remove oxygen present therein.
    Type: Grant
    Filed: September 20, 1973
    Date of Patent: March 23, 1976
    Assignee: Martin Marietta Corporation
    Inventor: Walter Precht