Nanoscale patterning of silicon dioxide thin films by catalyzed HF vapor etching

Carbon enhanced vapor etching (CEVE) is an alternative approach for fine pattern delineation in silicon dioxide, especially for nanolithographic processes. Exposures by a scanning electron microscope have achieved etch rates of about 16 nm min^-1 with etch selectivity ratios of 30 or greater for exposed to unexposed areas. Scanning tunneling microscope resolution studies have shown that trench widths on the order of 3-5 nm are possible. Pattern transfer to silicon has been achieved using reactive ion etching.