Patents by Inventor Maritza G. J. Heijman

Maritza G. J. Heijman 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: 4971948
    Abstract: In a method of manufacturing a device comprising a film of an oxide superconducting material which comprises an alkaline earth metal, another metal component, copper and oxygen. A superconductor precursor material comprising copper oxide, alkaline earth metal fluoride and another metal or metal oxide, is provided on a substrate in the form of a film. The film is covered with a diffusion barrier against water in accordance with a pattern which is complementary to a desired pattern of superconducting material. Subsequently, the superconducting material is formed in the uncovered portions of the pattern by means of a treatment at an increased temperature in the presence of water and oxygen.
    Type: Grant
    Filed: February 1, 1989
    Date of Patent: November 20, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Bernard Dam, Gerrit J. Van der Kolk, Maritza G. J. Heijman
  • Patent number: 4957899
    Abstract: A method is shown of applying in accordance with a pattern thin layers of an oxidic superconductive material onto a substrate in which a copper oxidic based material that after heating is rendered superconducting at a desired service temperature is covered in a desired pattern with a composition that renders the underlying oxidic material non-superconducting.
    Type: Grant
    Filed: January 3, 1989
    Date of Patent: September 18, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Maritza G. J. Heijman, Peter C. Zalm
  • Patent number: 4933318
    Abstract: A method of manufacturing a thin film of an oxidic superconducting material in accordance with a pattern, in which a pattern is manufactured by means of etching using reactive ions and a mask of aluminium oxide or silicon oxide, said method enabling patterns having line widths smaller than 2 .mu.m to be manufactured with great accuracy without influencing the composition of the superconducting thin film in such a manner that the superconducting properties deteriorate.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: June 12, 1990
    Assignee: U.S. Philips Corporation
    Inventor: Maritza G. J. Heijman
  • Patent number: 4931077
    Abstract: Grooves are etched in a glass substrate, using a metallic mask, after which the substrate is coated with a layer of glass having a refractive index which is higher than that of the substrate, the groove being filled completely. Excess glass is removed, the metallic mask being used as a stop layer and a protective layer being provided at the location of the filled grooves. Excess glass is removed at the location of the grooves by means of polishing so that a high accuracy as regards depth can be obtained.
    Type: Grant
    Filed: June 22, 1988
    Date of Patent: June 5, 1990
    Assignee: U.S. Philips Corp.
    Inventors: Johannes H. Angenent, Maritza G. J. Heijman, Gijsbertus A. C. M. Spierings
  • Patent number: 4900709
    Abstract: Method of applying in accordance with a pattern thin layers of oxidic superconductive material onto a substrate, it not being necessary to subject the superconductive material to mechanical or chemical treatments. At its surface the substrate is provided in accordance with a desired pattern with two different material compositions. The first composition is chosen such that the oxidic material applied thereon is superconductive at a desired surface temperature. The second composition is chosen such that the oxidic material applied thereon is not superconductive.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: February 13, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Maritza G. J. Heijman, Peter C. Zalm