Fabrication of sub-20 nm trenches in silicon nitride using CHF3/O2 reactive ion etching and oblique metallization

Abstract
A direct process for fabricating nanometer size trenches in Si3N4 using high voltage electron beam lithography and CHF3/O2 reactive ion etching has been developed and characterized. The process can be used on both bulk and thin membrane substrates and has demonstrated a feature resolution of better than 20 nm. An extension of this process allows 15 nm wide slots to be fabricated in a metal film without performing any metal etching.