Aberration measurement method, exposure apparatus, and device manufacturing method
US8345221B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2012 |
| Grant date | Jan 1, 2013 |
| Priority date | — |
| Expiry date | Apr 23, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/706
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for measuring a spherical aberration amount of a projection optical system that projects an image of a pattern formed on an original plate onto a substrate, includes: obtaining a first focal position in a direction of an optical axis of the projection optical system under a first measurement condition; obtaining a second focal position in the direction of the optical axis of the projection optical system under a second measurement condition; calculating the spherical aberration amount of the projection optical system based on a difference between the first focal position and the second focal position. Under the first measurement condition the focal position in the direction of the optical axis with respect to the spherical aberration amount does not change; and under the second measurement condition the focal position in the direction of the optical axis with respect to the spherical aberration amount changes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.