Projects per year
Molecular resists, such as triphenylene derivatives, are small carbon rich molecules, and thus give the potential for higher lithographic resolution and etch durability, and lower line width roughness than traditional polymeric compounds. Their main limitation to date has been poor sensitivity. A new triphenylene derivative molecular resist, with pendant epoxy groups to aid chemically amplified crosslinking, was synthesized and characterized. The sensitivity of the negative tone, pure triphenylene derivative when exposed to an electron beam with energy 20 keV was similar to 6 x 10(-4) C cm(-2), which increased substantially to similar to 1.5 X 10(-5) Ccm(-2) after chemical amplification (CA) using a cationic photoinitiator. This was further improved, by the addition of a second triphenylene derivative, to similar to 7 x 10(-6) C cm(-2). The chemically amplified resist demonstrated a high etch durability comparable with the novolac resist SAL 601. Patterns with a minimum feature size of similar to 40 nm were realized in the resist with a 30 keV electron beam.