Substrate for mirrors for EUV lithography

US8976927B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Claudia Ekstein · Ellwangen, DE
• Johannes Lippert · Buch am Wald, DE
• Holger Maltor · Aalen, DE
• Martin Weiser · Sinsheim, DE
• Heiko Siekmann · Aalen, DE
• Udo Dinger · Oberkochen, DE

Key dates

• Filing date: Feb 28, 2013
• Grant date: Mar 10, 2015
• Expiry date: Feb 28, 2033

Classification

• Technology area (CPC G): Physics
• CPC primary: G21K1/06
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Substrates suitable for mirrors which are used at wavelengths in the EUV wavelength range have a main body (2) and a polishing layer (3). The polishing layer (3) has a thickness of less than 10 μm and a root-mean-square roughness of less than 0.5 nm and the main body (2) is produced from an aluminum alloy. Moreover, a highly reflective layer (6) is provided on the polishing layer (3) of the substrate (1) of the EUV mirror (5).