Filter window, lithographic projection apparatus, filter window manufacturing method, device manufacturing method and device manufactured thereby
US7456932B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 2004 |
| Grant date | Nov 25, 2008 |
| Priority date | — |
| Expiry date | Mar 9, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/24
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A filter window for EUV lithography includes a pellicle, and a wire structure for supporting the pellicle. The pellicle includes a first layer that includes at least one of AlN, Ru, Ir, Au, SiN, Rh. The pellicle has a very low EUV absorption in combination with a minimal oxidation rate. The thickness of the pellicle may be between 30 nm and 100 nm. It can be easily checked that absorption of EUV radiation of such a thin pellicle is equal to known filter windows, i.e. about 50% at a wavelength of 13.5 nm wavelength, but the oxidation of the pellicle according to the invention is much smaller. The filter window can for example be used to separate a Projection Optics box and a wafer compartment of the apparatus or to shield a reticle from particle contamination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.