Alignment device and lithographic apparatus provided with such a device
US5917604A · kind A · utility
21Cited by
3References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1997 |
| Grant date | Jun 29, 1999 |
| Priority date | — |
| Expiry date | Mar 13, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A device is described for aligning a first object provided with a first alignment mark (P) with respect to a second object provided with a second alignment mark (M), which marks have a periodical structure and are imaged onto each other. By selecting beam portions from the radiation from the first alignment mark (P) with the aid of an order diaphragm (55'), which beam portions are deflected through larger angles, the sensitivity of the device to errors can be decreased. Such a device may be used to great advantage in a lithographic apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.