Alignment and exposure apparatus having an objective lens system capable of observing a mark on an exposure optical holding member to permit alignment of a mask relative to the exposure optical system
US4801808A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 1987 |
| Grant date | Jan 31, 1989 |
| Priority date | — |
| Expiry date | Jul 28, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An alignment system in an alignment and exposure apparatus for exposing a wafer to a pattern of a mask, for use in the manufacture of semiconductor devices, the alignment system including an objective lens system for observing alignment marks formed on the mask and the wafer respectively, in order to bring the mask and the wafer into a predetermined alignment relation, prior to the exposure of the wafer. The objective lens system is capable of observing a mark that is formed on a member for holding an exposure optical system in order to allow alignment of the mask relative to the exposure optical system, whereby a reference position of the objective lens system is determined on the basis of the mark formed on the holding member and whereby accurate movement of the objective lens system during movement thereof to a position for observing the alignment marks on the mask and the wafer is assured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.