Levelling device in an exposure apparatus
US4999669A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 1989 |
| Grant date | Mar 12, 1991 |
| Priority date | — |
| Expiry date | Jul 12, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70716
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure apparatus for forming a pattern of a mask on a photo-sensitive substrate comprises an X-Y stage, a Z-stage supported on the X-Y stage, and a levelling stage that supports the photo-sensitive substrate. The levelling stage is supported on the Z-stage by a plurality of levelling devices that define a levelling reference plane, and that are operated in unison to change the level of the levelling stage relative to the Z-stage and relative to an exposure reference plane that is parallel to the levelling reference plane. The levelling devices are also operated individually to change the inclination of the photo-sensitive substrate relative to the levelling reference plane and relative to the exposure reference plane. A focus detector controls the movement of the Z-stage and the in-unison movement of the levelling devices. An inclination detector controls the individual operation of the levelling devices. The net result is that the surface of the photo-sensitive substrate is made coincident with the exposure reference plane and the levelling reference plane, and the center point of the surface of the photo-sensitive substrate becomes the pivotal center for changes in inclinati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.