Patents by Inventor Koshi Tamamura

Koshi Tamamura 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).

  • Determination of critical film thickness of a compound semiconductor layer, and a method for manufacturing a semiconductor device using the method of determination
    Patent number: 5695556
    Abstract: By applying the method, the critical film thickness of a compound semiconductor layer is determined, and a semiconductor device having a compound semiconductor layer with an optimized film thickness excellent in emitting performance is manufactured.The relationship between film thickness of a compound semiconductor layer and photoluminescence (PL) corresponding to the film thickness is obtained by measurement, the film thickness where PL exhibits a peak is designated as critical film thickness. The semiconductor layer comprises II-VI group compound semiconductor layer containing at least cadmium. The relationship between the critical film thickness and cadmium composition ratio is obtained by measurement. An equation which approximates the relationship between the critical film thickness and cadmium composition ratio is formulated.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: December 9, 1997
    Assignee: Sony Corporation
    Inventors: Koshi Tamamura, Hironori Tsukamoto, Masaharu Nagai, Masao Ikeda