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:
May. 24, 1994
Filed:
Sep. 25, 1992
Hiroyuki Itoh, Katsuta, JP;
Minoru Sasaki, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Drift values of exposure position of an electron beam are obtained through detection of a reference mark on a sample stage and a drift characteristic formula which expresses the exposure positions of the electron beam is corrected by using a plurality of the drift values. The electron beam is controlled to expose some lithographic pattern by estimating the exposure position in real time at which the electron beam is irradiated at the estimated exposure position based on the drift characteristic formula without detecting the reference mark, and further to expose other lithographic pattern by calculating the exposure position based on the drift characteristic formula by detecting the reference mark. The measuring of the drift which takes much time are partly taken place at few limitted positions and the correction of the exposure positions is effectively in a short time.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile