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. 26, 2007
Filed:
Jun. 29, 2004
Do-yul Yoo, Gyeonggi-do, KR;
Do-yul Yoo, Gyeonggi-do, KR;
Samsung Electronics Co., Ltd., Suwon-si, Gyeonggi-do, KR;
Abstract
An overlay key includes a main scale and a vernier scale, which traverse each other forming a plurality of crossings. The main scale includes a first main sub-scale and a second main sub-scale, which are separated from each other or at least partially overlap each other. The first and second main sub-scales extend in different directions such that they are not parallel to each other. The vernier scale includes a first vernier sub-scale and a second vernier sub-scale, which are separated from each other or at least partially overlap each other. The first and second vernier sub-scales extend in different directions such that they are not parallel to each other. Two measured crossings are obtained when the main scale and the vernier scale cross each other in a measured position. Then, overlay accuracy is measured from coordinate differences between reference crossings and the measured crossings.