10 nm scale electron beam lithography using a triphenylene derivative as a negative/positive tone resist

Abstract
We show that the liquid crystal triphenylene derivative 2,3,6,7,10,11-hexapentyl-oxytriphenylene acts as a high-resolution electron beam resist. Using pentanol as a developer, positive behaviour was observed for electron doses greater than ~300µC cm-2 at 20 keV. At higher doses (>2.5 mC cm-2), the resist rapidly assumes negative tone behaviour. With the developer monochlorobenzene, only negative behaviour was observed, with a sensitivity of ~2.5 mC cm-2 at 20 keV. The resist allows relatively facile definition of 14 nm patterns (negative tone) with a 30 keV electron beam and without the need for any complex pre-irradiation preparation or post-irradiation processing of the resist.