Pattern exposure apparatus with distance measuring system
US4659225A · kind A · utility
36Cited by
1References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 11, 1985 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | Apr 11, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70691
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure apparatus wherein a semiconductor wafer is exposed to an IC circuit pattern formed on a mask through a reduction projection optical system, and then the wafer is stepped; and these operations are alternately repeated, thereby forming a plurality of patterns on the wafer. A distance measuring system utilizing the interference between laser beams, has a first mirror fixed relative to the mask and another mirror fixed relative to the wafer, so that the relative position between the mask and the wafer is determined by a single interferometer system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.