Lithographic apparatus, device manufacturing method, and device manufactured thereby
US6819425B2 · kind B2 · utility
129Cited by
35References
35Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 22, 2001 |
| Grant date | Nov 16, 2004 |
| Priority date | — |
| Expiry date | Aug 20, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7053
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The X, Y and Rx positions of a mask stage are measured using two optical encoder-reading heads measuring displacements of respective grid gratings mounted on the mask stage. The grid gratings are preferably provided on cut-away portions of the mask table so as to be co-planar with the pattern on the mask itself. Measurements of the table position in the other degrees of freedom can be measured with capacitative or optical height sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.