Pattern transfer of electron beam modified self-assembled monolayers for high-resolution lithography

Abstract

Self-assembled monolayers of octadecylsiloxane and octadecylthiol have been modified by high-resolution electron beam lithography. Focused electron beams from 1 to 50 keV and scanning tunneling microscopy at ∼10 eV have been used as patterning tools. The patterns have been transferred into many substrates by wet, dry, and combinations of wet and dry etches. Wet etching almost always results in a positive tone, but reactive ion etching of GaAs with Cl2 at very low dc biases (<10 V) results in a negative tone. The effect of electron beam damage on the monolayers and the subsequent etching reactions has been explored through x-ray photoelectron spectroscopy.