Patents by Inventor Michel Pierschel

Michel Pierschel 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).

  • Procedure for the manufacture of bipolar transistors without epitaxy and with fully implanted base and collector regions which are self-positioning relative to each other
    Patent number: 5571731
    Abstract: A method of fabricating a semiconductor device. A series of layers is deposited on a semiconductor substrate of a first conductivity type to form a shielding arrangement, including an upper part and a lower part, to provide a shield against accelerated ions. This is followed by forming openings in the shielding arrangement by microlithographic processes and anisotropic etching, and then implanting ions via the openings to form one of a base area and a base-connection area of the first conductivity type. Edges of the openings are displaced by isotropic etching of the lower part of the shielding arrangement.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: November 5, 1996
    Assignee: PREMA Pr azisionselektronik GmbH
    Inventors: Hartmut Gr utzediek, Joachim Scheerer, Wolfgang Winkler, Michel Pierschel, Karl-Ernst Ehwald