Amphoteric Doping Patents (Class 148/DIG2)
  • Patent number: 4939102
    Abstract: 36 We have discovered the III-V semiconductor layers with previously unattainably high effective hole concentrations can be produced by molecular growth processes (e.g. MBE) if an amphoteric dopant such as Be is used and if, during the growth of the highly doped III-V layer, the substrate is maintained at a temperature T.sub.g that is substantially lower than customarily used. For instance, a InGaAs layer with effective hole concentration 1.0.times.10.sup.20 cm.sup.-3 was grown at T.sub.g =450.degree. C., and a GaAs layer with effective hole concentration of 1.0.times.10.sup.20 cm.sup.-3 was grown at T.sub.g of 475.degree. C. The heavily doped III-V layers can be of device grade and can usefully be part of electronic devices such as high speed bipolar transistors.
    Type: Grant
    Filed: January 17, 1989
    Date of Patent: July 3, 1990
    Assignee: American Telephone and Telegraph Company
    Inventors: Robert A. Hamm, Roger J. Malik, Morton B. Panish, John F. Walker
  • Patent number: 4847216
    Abstract: The process consists of depositing at least one layer of a doped material on a heated substrate placed in an enclosure, subjecting the substrate surface to the action of a molecular flux of the material, to the action of a doping particle beam and to the action of an electron beam.
    Type: Grant
    Filed: April 18, 1988
    Date of Patent: July 11, 1989
    Assignee: Centre National d'Etudes des Telecommunications
    Inventors: Francois A. d'Avitaya, Yves Campidelli