Apertured window for enabling flexible illumination overfill of patterning devices
US8064122B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 15, 2007 |
| Grant date | Nov 22, 2011 |
| Priority date | — |
| Expiry date | Jun 9, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70941
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A dark border region may be integrated with a window covering a patterning device, such that light from an active area of the patterning device passes through the dark border region, while excess light is removed from the system by the dark border region. The dark border region may be, for example and without limitation, a light-absorbing material, a wedged light reflective coating that reflects light out of the lithography system, or an interference grating that causes destructive interference in unwanted light to remove the unwanted light from the system. The dark border region may overlap a similar dark border region located on the surface of on the patterning device to optimize a width of the total dark border region without sacrificing excessive valuable real-estate area on the surface of the patterning device or compromising alignment tolerance levels of the lithography system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.