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:
Mar. 05, 1996
Filed:
Jun. 08, 1994
Nobuyuki Iriki, Kodaira, JP;
Tsutomu Okabe, Kodaira, JP;
Kenji Watanabe, Ohme, JP;
Hisashi Maejima, Higashiyamato, JP;
Shinji Kuniyoshi, Tokyo, of, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor integrated circuit device fabrication technique improves the accuracy of element qualities by considering the influence of interaction of element quality parameters in the quality control of semiconductor fabrication processes and also by improving the product yield estimation accuracy so that the production efficiency can be improved. An initial value of a membership function is first set and then a plurality of element quality parameters and a combined quality parameter are expressed by membership functions in fuzzy control in a semiconductor fabrication apparatus for automating a fabrication method by connecting a computer with various measuring instruments and various processors by communication devices. Moreover, the combined quality parameters are fuzzy-inferred from the element quality parameters using these membership functions, inference rules are adjusted by data of the actual processes, the membership functions of the obtained element quality parameters are converted into an element quality control standard, and the semiconductor integrated circuit device fabrication processes are controlled in accordance with the standard.