As commercialization of extreme ultraviolet lithography (EUVL) progresses, direct industry activities are being focused
on near term concerns. The question of long term extendibility of EUVL, however, remains crucial given the magnitude
of the investments yet required to make EUVL a reality. Extendibility questions are best addressed using advanced
research tools such as the SEMATECH Berkeley microfield exposure tool (MET) and actinic inspection tool (AIT).
Utilizing Lawrence Berkeley National Laboratory's Advanced Light Source facility as the light source, these tools
benefit from the unique properties of synchrotron light enabling research at nodes generations ahead of what is possible
with commercial tools.
The MET for example uses extremely bright undulator radiation to enable a lossless fully programmable coherence
illuminator. Using such a system, resolution enhancing illuminations achieving k1 factors of 0.25 can readily be attained.
Given the MET numerical aperture of 0.3, this translates to an ultimate resolution capability of 12 nm. Using such
methods, the SEMATECH Berkeley MET has demonstrated resolution in resist to 16-nm half pitch and below in an
imageable spin-on hard mask. At a half pitch of 16 nm, this material achieves a line-edge roughness of 2 nm with a
correlation length of 6 nm. These new results demonstrate that the observed stall in ultimate resolution progress in
chemically amplified resists is a materials issue rather than a tool limitation. With a resolution limit of 20-22 nm, the
CAR champion from 2008 remains as the highest performing CAR tested to date.
To enable continued advanced learning in EUV resists, SEMATECH has initiated a plan to implement a 0.5 NA
microfield tool at the Advanced Light Source synchrotron facility. This tool will be capable of printing down to 8-nm