Patents by Inventor Pravin C. Parekh

Pravin C. Parekh 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).

  • Method for compensating for emitter-push effect in the fabrication of transistors
    Patent number: 4006046
    Abstract: A semiconductor wafer having a base dopant source disposed on its surface receives a surface coating consisting of, for example, a silicon nitride film. An emitter opening is formed in the silicon nitride surface coating and a portion of the base dopant source is stripped away within the emitter opening. Diffusion of the base region will result in predetermined geometrical regions of varying concentration of the base dopant as a result of the surface coating and the effect of the oxidizing atmosphere. Subsequent deposition and diffusion of the emitter region provides for smaller base widths and eliminates the need for subsequent deposition and diffusion of high concentration base dopant contact regions.
    Type: Grant
    Filed: April 21, 1975
    Date of Patent: February 1, 1977
    Assignee: TRW Inc.
    Inventor: Pravin C. Parekh