Tri-layer process is the one of the key technique both for lithography and etching around Hp20nm patterning. In
applying for tri-layer process, we are focusing on inorganic type under layer which mainly containing Si atoms. This Si
type hard mask (Si-HM) can perform not only as the Lithography performance enhancement layer for fine pitch, but also
as the etching hard mask against bottom layer (spin on carbon : SOC). In this paper, we propose our new Si-HM
concepts to achieve high sensitivity, wide process window and good line edge roughness for hp 1Xnm generation. The
key point of our concepts is EUV sensitive unit in Si-HM. Our EUV sensitive unit strongly promotes acid generation
from PAG of EUV photo resist. Especially, for EUV NTD lithography process, EUV sensitive unit can perform as the
adhesion enhancer between Si-HM and photo resist at EUV exposed area.
As this result, hp18nm L/S pattern and hp24nm C/H pattern were successfully achieved by applying the EUV
sensitive Si-HM in EUV PTD process. Especially, as compared to organic UL, the 4th generation EUV sensitive Si-HM
showed 5~10% higher sensitivity and 10~25% wider process window (DOF and EL) with keeping LER. Moreover this
EUV-sensitive Si-HM could also enhance the ultimate resolution to Hp22nm L/S in EUV NTD process. On the other
hand, from the view point of etching hard mask, around hp 19 nm Si-HM L/S pattern could be transferred to SOC layer
successfully. We will present the high resolution concepts and performances of our latest EUV sensitive Si-HM for 1X
nm generation in EUV lithography.