Nano-imprint lithography (NIL) is eminently suitable for low cost patterning for nanostructures. As feature
sizes of the UV-NIL templates are the same as the wafer patterns, there are enormous challenges such as writing and
inspecting smaller patterns for NIL template fabrication. In our previous works, we achieved less than 16nm resolution
with a 100keV spot beam writer and non CAR. We also reported optimization of metrology for NIL templates and the
characterization of anti-sticking layers with scanning probe microscopies.
Normally the template is made from a 6025 photomask blank. After the blank undergoes a process similar to
the photomask process, it is diced into 65 mm x 65 mm size and four pieces, and then each piece is polished into its final
shape. Therefore it becomes difficult to inspect and clean them, because 65 mm substrates are unfamiliar in photomask
industry. In order to reach the step for mass-production of the templates, the development of "back-end process", which
includes not only cleaning and inspection but also repair, dicing, polishing, and coating anti-sticking layers, is essential.
Especially keeping low contamination level during dicing and polishing processes is one of the critical issues.
In this paper, we report our development status of "back-end process" for NIL templates. Especially, we focus
on the techniques of reducing adder defects during dicing process and improving cleaning capability.