Patents by Inventor Sukhdev S. Gill

Sukhdev S. Gill 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).

  • Ni-Ge-Au ohmic contacts for GaAs and GaAlAs
    Patent number: 5309022
    Abstract: A low resistance ohmic contact for n-type GaAs and GaAlAs is provided by Ni-Ge-Au structure (1). The contact is suitable for device substrates (2) which have carrier concentrations of between about 10.sup.17 cm.sup.-3 and about 10.sup.19 cm.sup.-3. The ohmic contact has a nickel layer of between 40 .ANG. and 200 .ANG. deposited on the substrate, followed by a Ge deposition (4) of between 150 .ANG. and 400 .ANG. and finally an Au deposition (5, 6) of greater than 4000 .ANG.. The Au layer is preferably deposited in two separate layers of between 500 .ANG. and 1000 .ANG., (5), and greater than 4000 .ANG., (6). A preferred construction (1) is 50 .ANG./200 .ANG./800 .ANG.+5000 .ANG. (Ni/Ge/Au+Au). The ohmic contact deposition must be followed by annealing, typically at temperatures between 300.degree. C. and 500.degree. C. for times of between 1 second and 200 seconds. The preferred annealing conditions are a temperature of 400.degree. C. maintained for 15 seconds.
    Type: Grant
    Filed: February 14, 1992
    Date of Patent: May 3, 1994
    Assignee: The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
    Inventors: Sukhdev S. Gill, Mark A. Crouch, John R. Dawsey