The availability of defect-free masks remains one of the key challenges for inserting extreme ultraviolet lithography (EUVL) into manufacturing. Evidently, the success of the industry's mask blank defect reduction effort will critically depend on the timely availability of defect inspection tools that can find ever smaller defects. The first generation of defect inspection tools enabled SEMATECH's Mask Blank Development Center (MBDC) to reduce mask blank defects to a level sufficient for use in EUV alpha tools. The second tool generation is currently enabling the MBDC to meet EUV pilot line requirements by the end of 2007. However, to meet high volume manufacturing (HVM) mask blank defect requirements for 32 nm half-pitch (hp) patterning, the industry needs a third generation of defect inspection tools. This next EUV inspection tool generation must be able to find defects of ≤ 20 nm on mask blanks with a high capture rate and high blank throughput. In addition, these tools will also need to support extendibility assessments of low defect deposition technologies and the associated infrastructure towards meeting 22 nm half-pitch defect specifications. While visible light inspection is likely to support defect inspection needs for mask substrates over several technology nodes, the industry must explore other options for mask blanks and patterned masks. Evaluating the use of inexpensive printing tools and wafer-based inspection to search for repeating defects must be part of an overall strategy to address mask blank and patterned mask defect inspection.

Date Published: 15 May 2007
PDF: 9 pages
Proc. SPIE 6607, Photomask and Next-Generation Lithography Mask Technology XIV, 66073A (15 May 2007); doi: 10.1117/12.729029

Published in SPIE Proceedings Vol. 6607:
Photomask and Next-Generation Lithography Mask Technology XIV
Hidehiro Watanabe, Editor(s)