Exposure apparatus
US5798822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1997 |
| Grant date | Aug 25, 1998 |
| Priority date | — |
| Expiry date | Oct 15, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A pair of reference plates is so arranged as to have a predetermined positional relationship on a carriage that integrally holds a mask and a photosensitive substrate such that the mask and the photosensitive substrate oppose each other on two sides of a projecting optical system. By periodically detecting the positional relationship between the reference plates in the optical axis direction, a variation with time occurring in the detection characteristics of position detecting devices is detected. Both stable image formation characteristics and a high throughput are realized by correcting a driving signal to be supplied to a driving device in accordance with the detected variation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.