Projection lithography system and method using all-reflective optical elements
US5686728A · kind A · utility
117Cited by
4References
20Claims
0Family size
Inventor
Key dates
| Filing date | May 1, 1996 |
| Grant date | Nov 11, 1997 |
| Priority date | — |
| Expiry date | May 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70275
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection lithographic system that operates within the deep ultraviolet to vacuum ultraviolet region of the spectrum and uses an all-reflective optical arrangement to project a reduced image of a lithographic mask onto a semiconductor wafer. The all-reflective optical arrangement includes from six to eight reflective surfaces wherein each of the reflective surfaces is aspheric, The reflective surfaces are disposed along a common optical axis and are arranged not to interfere with the path of light as the light travel from the lithographic mask to the semiconductor wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.