NANOSCALE SCANNING TUNNELING MICROSCOPE PATTERNING OF SILICON DIOXIDE THIN-FILMS BY CATALYZED HF VAPOR ETCHING

We report on the use of electron beam and scanning tunneling microscope (STM) patterns of ambient hydrocarbon residues on silicon dioxide as chemical initiators for the localized high-temperature HF vapor etching of oxide thin films. The treated films, when subjected to HF vapor etching at 115 °C, are patterned in the areas that have been exposed to an electron beam in either a scanning electron microscope or STM. The technique has been combined with reactive ion etching or metallization to yield nanometer scale patterns and nanoscale metal silicide lines on silicon. Nonaqueous Bronsted bases have been shown to be retained on the oxide surface at temperatures of up to 125 °C and to function as HF etch initiators. Such species show promise as monolayer resists for the patterning of silicon dioxide using the HF vapor etch process.