The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 1992
Filed:
Aug. 23, 1991
Tatsuo Moroi, Kudamatsu, JP;
Keiji Tada, Kudamatsu, JP;
Noriaki Yamamoto, Kudamatsu, JP;
Tetsunori Kaji, Kudamatsu, JP;
Gen Marumoto, Kudamatsu, JP;
Yuzou Ohhirabaru, Kudamatsu, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method of detecting an end point of etching by emission spectroscopy. Using a constant ratio between emission intensities in the course of etching and after the termination thereof, a correction value is computed with data of a waveform already adjusted to be capable of detecting an end point of etching and the corresponding emission intensity in the course of etching treatment thereafter, and the waveform of corresponding emission intensity in the course of etching treatment is processed so that the detection can be conducted on the same level as in the end point detection already adjusted to be capable of detecting the end point of etching at the time of treatment. Thus, irrespective of the reduction of the quantity of emission for an emission detection at each time of treatment, a constant electric signal of the same detecting level can be obtained, making it possible to detect an end point of etching with the same accuracy as in the initial treatment.