Sol–gel processing of silicon nitride films from Si(NHMe)4 and ammonia

Abstract

The formation of silicon nitride films using a sol–gel process and dip-coating is reported. The effect of a trifluoromethanesulfonic acid catalyst on condensation is investigated, and affects the behaviour of gels on heating. Smooth films can be obtained on silicon wafer substrates, and these can be built up using multiple dippings as the gelation process is irreversible. Firing at 1000 °C produces amorphous silicon nitride films, though these contain some carbon and hydrogen and are sensitive to surface oxidation.