抄録
EUV lithography has been used for high-volume manufacturing of semiconductor devices since 2019.
An EUV lithography photomask is a reflection type with Mo/Si multilayer coatings. Since the EUV reflection
phase is critical for printability, actinic (at-wavelength) inspection tools and microscopes were
developed. In this report, we introduce an EUV specific issue of photomasks and EUV inspection tools
for high-volume manufacturing. An EUV microscope is also important for EUV mask development. We
made coherent EUV scatterometry microscopes to observe EUV phase images, which captured EUV diffraction
from mask patterns without imaging optics. EUV phase images will be helpful for the development
of high-contrast EUV masks.
