Recently, most of defects on high-end masks are repaired with electron beam (EB). The minimum repairable dimension of the current state-of-the-art repair systems is about 20-30 nm, but that dimension is not small enough to repair the next generation masks. Meanwhile, new molybdenum silicide (MoSi) films with high cleaning durability are going to be provided for an alternative technology, but the etching selectivity between new MoSi and quartz under EB repair process is not high enough to control etching depth. We developed the focused ion beam (FIB) technology that uses light ions emitted from a gas field ion source (GFIS). In this study, the performance of our developed GFIS mask repair system was investigated by using new MoSi (HOYA-A6L2). Specifically, the minimum repairable dimension, image resolution, imaging damage, etching material selectivity and through-focus behavior on AIMS were evaluated. The minimum repairable dimension was only 11 nm that is nearly half of that with EB. That result suggests that GFIS technology is a promising candidate for repairing the next generation masks. Meanwhile, the etching selectivity between A6L2 and quartz was 6:1. Additionally, the other evaluations on AIMS showed good results. Those results demonstrate that GFIS technology is a reliable solution of repairing new MoSi masks with high cleaning durability.
[1]
Osamu Suga,et al.
Development of new FIB technology for EUVL mask repair
,
2011,
Advanced Lithography.
[2]
Osamu Suga,et al.
Prospect of EUV mask repair technology using e-beam tool
,
2010,
Photomask Technology.
[3]
Paul Alkemade,et al.
Nanofabrication with a helium ion microscope
,
2010,
Advanced Lithography.
[4]
Nicholas P. Economou,et al.
Helium ion microscope: A new tool for nanoscale microscopy and metrology
,
2006
.
[5]
T. Bret,et al.
Repair of natural EUV reticle defects
,
2011,
Photomask Technology.