Thermally stable multilayer mirror for the EUV spectral region

US7920323B2 · kind B2 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Nicolas Benoit · Gießen, DE
• Torsten Feigl · Jena, DE
• Norbert Kaiser · Markt Taschendorf, DE
• Sergiy Yulin · Jena, DE

Key dates

• Filing date: Dec 23, 2005
• Grant date: Apr 5, 2011
• Expiry date: Nov 15, 2027

Classification

• Technology area (CPC G): Physics
• CPC primary: G21K2201/067
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In a multilayer mirror (1) for the reflection of EUV radiation containing a large number of alternating molybdenum layers (4) and silicon layers (3), a barrier layer (5) containing a silicon nitride or a silicon boride is included at a number of interfaces between the molybdenum layers (4) and the silicon layers (3). As a result of the barrier layers (5) of a silicon nitride or of a silicon boride, high thermal stability is achieved, in particular high long-term stability at temperatures of more than 300° C., whilst at the same time achieving high reflectivity in the multilayer mirror. A multilayer mirror (1) of this type can, in particular, be used as a heatable collector mirror for an EUV radiation source.