Optimized capping layers for EUV multilayers

Patent · Tue Aug 24 00:00:00 EDT 2004

OSTI ID:921905

Bajt, Sasa ^[1]; Folta, James A ^[1]; Spiller, Eberhard A ^[1]

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1. Livermore, CA

A new capping multilayer structure for EUV-reflective Mo/Si multilayers consists of two layers: A top layer that protects the multilayer structure from the environment and a bottom layer that acts as a diffusion barrier between the top layer and the structure beneath. One embodiment combines a first layer of Ru with a second layer of B.sub.4 C. Another embodiment combines a first layer of Ru with a second layer of Mo. These embodiments have the additional advantage that the reflectivity is also enhanced. Ru has the best oxidation resistance of all materials investigated so far. B.sub.4 C is an excellent barrier against silicide formation while the silicide layer formed at the Si boundary is well controlled.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• Assignee: EUV LLC (Santa Clara, CA)
• Patent Number(s): 6,780,496
• Application Number: 10/066,108
• OSTI ID: 921905
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE