Alignment system
US5112133A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1991 |
| Grant date | May 12, 1992 |
| Priority date | — |
| Expiry date | Oct 1, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/682
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An alignment system usable in an exposure apparatus for printing a pattern of a mask on a wafer, for aligning the mask and the wafer, is disclosed. The system includes a plurality of position detecting devices; a plurality of driving stages corresponding to the position detecting devices, respectively, each driving stage being adapted to move a corresponding one of the position detecting devices two-dimensionally along a plane which is substantially opposed to the mask; a plurality of contacts corresponding to the position detecting devices, respectively, each contact being provided at an end portion of a corresponding one of the position detecting devices, along the plane and facing the pattern side; a detecting device for detecting mutual approach of the position detecting devices through at least one of the contacts; and a control device for controlling movement of at least one of the driving stages in accordance with the detection by the detecting device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.