Abstract: The present invention relates to a method of and apparatus for detecting the end point of plasma treatment. The method includes steps: selecting a plasma spectrum having a characteristic wavelength from the plasma spectrum occurring at the time of the plasma treatment reaction of a specimen; computing a secondary differential value of a function of the quantity of the plasma spectrum selected and the plasma treatment reaction time of the specimen; and detecting the end point of the plasma treatment reaction of the specimen by comparing the secondary differential value computed with preset reference values for judgment.
Type:
Grant
Filed:
March 15, 1985
Date of Patent:
October 7, 1986
Assignees:
Hitachi, Ltd., Hitachi Sanki Eng Co., Ltd.
Inventors:
Keiji Tada, Takashi Fujii, Gen Marumoto, Kazuhiro Jyouo, Takahiro Fujisawa