Patents by Inventor Kazumi Takemura

Kazumi Takemura 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 of gettering semiconductor wafers with an excimer laser beam
    Patent number: 4782029
    Abstract: A gettering method has a step in which the back surface of a semiconductor substrate having the upper surface on which semiconductor device elements is to be formed, with a laser beam having a wavelength of 150 to 400 nm to introduce strain fields onto the back surface of the substrate. The energy density of the laser beam is from 0.5 to 10 J/cm.sup.2, and the irradiation pitch of the laser is 40 to 1500 .mu.m. The laser irradiation may be effected under the condition where an oxide film or a nitride film is formed on the back surface of the semiconductor substrate, or after the back surface of the semiconductor substrate is blasted with fine particles of silica or the like.
    Type: Grant
    Filed: June 30, 1987
    Date of Patent: November 1, 1988
    Assignee: NEC Corporation
    Inventors: Kazumi Takemura, Fumitoshi Toyokawa, Masao Mikami