Patents by Inventor Lawrence F. Latham

Lawrence F. Latham 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: 5837590
    Abstract: A vertical PNP transistor and method for making it provide a transistor in a surface layer (12), which may be an epitaxial layer, of P- type conductivity at a surface of a substrate (11) of P+ type conductivity. An isolation region (14) of N- type conductivity in the P- surface layer (12) contains a collector region (25) of P- type conductivity. A base region (30) of N type conductivity is contained in the collector region (25), and an emitter region (40) of P+ type conductivity is contained in the base region (30). The base region (30) may be provided with a higher N type impurity concentration than a P type impurity concentration of the collector region (25). At least the collector region (25) and the base region (30) may be self aligned. The collector region (25) may be of thickness of about 2.2 .mu.m, the base region (30) of thickness of about 0.1 .mu.m, and the emitter region (40) of thickness of about 0.4 .mu.m.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: November 17, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Lawrence F. Latham, Theresa M. Keller