Currently, we are supplying defect-free EUV mask for device development. This was one of the biggest challenges in the implementation of EUV lithography for high volume manufacturing (HVM). It became possible to hide all multi-layer defects by using defect avoidance technique through improvement of blank mask defectivity and development of actinic blank inspection tool. In addition, EUV pellicle is also considered as a requisite to guarantee predictable yield. Both development of mask shop tools and preparation of EUV scanner for pellicle are going well. However, still membrane needs to be much improved in terms of transmittance and robustness for HVM. At the conference, EUV mask readiness for HVM will be discussed including blank defect improvement, preparation of actinic tools and pellicle development.
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