Patents by Inventor Fred Ju

Fred Ju 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: 4846926
    Abstract: A layer of HgCdTe (15) epitaxially grown on a crystalline support (10). A single crystal CdTe substrate (5) is first epitaxially grown to a thickness of between 1 micron and 5 microns onto the support (10). Then a HgTe source (3) is spaced from the CdTe substrated (5) a distance of between 0.1 mm and 10 mm. The substrate (5) and source (3) are heated together in a thermally insulating, reusable ampoule (17) within a growth temperature range of between 500.degree. C. and 625.degree. C. for a growth time of between 5 minutes and 13 hours. In a first growth step embodiment, the source (3) and substrate (5) are isothermal. In a second growth step embodiment, the source (3) and substrate (5) are non-isothermal. Then an optional interdiffusion step is performed, in which the source (3) and substrate (5) are cooled within a temperature range of between 400.degree. C. and 500.degree. C. for a time of between 1 hour and 16 hours.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: July 11, 1989
    Assignee: Ford Aerospace & Communications Corporation
    Inventors: Robert E. Kay, Hakchill Chan, Fred Ju, Burton A. Bray
  • Patent number: 4743310
    Abstract: A layer of HgCdTe (15) is epitaxially grown on a crystalline support (10). A single crystal CdTe substrate (5) is first epitaxially grown to a thickness of between 1 micron and 5 microns onto the support (10). Then a HgTe source (3) is spaced from the CdTe substrate (5) a distance of between 0.1 mm and 10 mm. The substrate (5) and source (3) are heated together in a thermally insulating, reusable ampoule (17) within a growth temperature range of between 500.degree. C. and 625.degree. C. for a growth time of between 5 minutes and 13 hours. In a first growth step embodiment, the source (3) and substrate (5) are non-isothermal. In a second growth step embodiment, the source (3) and substrate (5) are isothermal. Then an optional interdiffusion step is performed, in which the source (3) and substrate (5) are cooled within a temperature range of between 400.degree. C. and 500.degree. C. for a time of between 1 hour and 16 hours.
    Type: Grant
    Filed: February 2, 1987
    Date of Patent: May 10, 1988
    Assignee: Ford Aerospace & Communications Corporation
    Inventors: Robert E. Kay, Hakchill Chan, Fred Ju, Burton A. Bray
  • Patent number: 4655848
    Abstract: A layer of HgCdTe (15) epitaxially grown onto a crystalline support (10), e.g., of sapphire of GaAs. A CdTe substrate (5) is epitaxially grown to a thickness of between 1 micron and 5 microns on the support (10). A HgTe source (3) is spaced from the CdTe substrate (5) a distance of between 0.1 mm and 10 mm. The substrate (5) and source (3) are heated together in a thermally insulating, reusable ampoule (17) within a growth temperature range of between 500.degree. C. and 625.degree. C. for a growth step having a duration of between 5 minutes and 4 hours. Then an interdiffusion step is performed, in which the source (3) and substrate (5) are cooled within a temperature range of between 400.degree. C. and 500.degree. C. for a time of between 1 hour and 16 hours. In a first growth step embodiment, the source (3) and substrate (5) are isothermal. In a second growth step embodiment, the source (3) and substrate (5) are non-isothermal.
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: April 7, 1987
    Assignee: Ford Aerospace & Communications Corporation
    Inventors: Robert E. Kay, Hakchill Chan, Fred Ju, Burton A. Bray
  • Patent number: 4648917
    Abstract: A layer of HgCdTe (15) is epitaxially grown onto a CdTe substrate (5). A HgTe source (3) is spaced from the CdTe substrate (5) a distance of between 0.1 mm and 10 mm. The substrate (5) and source (3) are heated within a temperature range of between 500.degree. C. and 625.degree. C. for a processing step having a duration of between 5 minutes and 4 hours. During at least 5 minutes of this processing step, the substrate (5) is made to have a greater temperature than the source (3). Preferably the substrate (5) is never at a lower temperature than the source (3). The source (3) and substrate (5) are heated together in a thermally insulating, reusable ampoule (17). The CdTe substrate (5) is preferably a thin film epitaxially grown on a support (10) e.g., of sapphire or GaAs. When support (10) is not used, the CdTe substrate (5) is polished; and sublimation and solid state diffusion growth mechanisms are present in the growth of the HgCdTe (15).
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: March 10, 1987
    Assignee: Ford Aerospace & Communications Corporation
    Inventors: Robert E. Kay, Hakchill Chan, Fred Ju, Burton A. Bray