Alignment method utilizing plurality of marks, discriminable from each other, capable of effecting alignment individually
US5849441A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1997 |
| Grant date | Dec 15, 1998 |
| Priority date | — |
| Expiry date | Feb 3, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/975
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In order to provide a search alignment method capable of high-speed alignment without a relative movement between an alignment system and a substrate, an alignment mark is constituted by a plurality of element marks having shapes different from each other, the plurality of element marks are provided in such a manner that each two of them has a gap a little shorter than the size of the field of view of the alignment system therebetween, and if even one of the element marks constituting the alignment mark comes into the field of view of the alignment system, said element mark is identified out of all of said element marks, whereby the position of the entire alignment is measured from the position of said one element mark. Therefore, if the alignment mark is moved in a range wider than the field of view of the alignment system, it is possible to detect the position of the alignment mark by one measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.