  The temperature dependence of the electron-beam sensitive resist CSAR 62 is
investigated in its negative-tone regime. The writing temperatures span a wide
range from 4 K to room temperature with the focus on the liquid helium
temperature regime. The importance of low temperature studies is motivated by
the application of CSAR 62 for deterministic nanophotonic device processing by
means of in-situ electron-beam lithography. At low temperature, CSAR 62
exhibits a high contrast of 10.5 and a resolution of 49 nm. The etch stability
is almost temperature independent and it is found that CSAR 62 does not suffer
from peeling which limits the low temperature application of the standard
electron-beam resist PMMA. As such, CSAR 62 is a very promising negative-tone
resist for in-situ electron-beam lithography of high quality nanostructures at
low temperature.
