Atomic-hydrogen cleaning of Sn from Mo/Si and DLC/Si extreme ultraviolet multilayer mirrors

作者：Soer Wouter A^*; van Herpen Maarten M J W; Jak Martin J J; Gawlitza Peter; Braun Stefan; Salashchenko Nikolay N; Chkhalo Nikolay I; Banine Vadim Y

来源：Journal of Micro/ Nanolithography, Mems, and Moems, 2012, 11(2): 021118.

DOI：10.1117/1.JMM.11.2.021118

• EUV
• lithography
• multilayer mirror
• spectral purity
• Sn cleaning
• hydrogen etching
• tin hydride

We have investigated the use of atomic-hydrogen-based cleaning to remove Sn contamination from extreme ultraviolet (EUV) multilayer mirrors. Mo and Si surfaces were cleaned at a relatively slow rate due to catalyzed dissociation of tin hydride on these surfaces. Mo/Si mirrors with B4C and Si3N4 cap layers and DLC-terminated DLC/Si mirrors showed complete removal of 10 nm Sn in 20 sec with full restoration of EUV reflectance. In addition, a prolonged cleaning treatment of 300 sec of a DLC/Si mirror resulted in only a minor EUV peak reflection loss of 1.2% absolute and no significant changes in infrared reflectance.

• 出版日期2012-6