CHARACTERIZATION OF WAFER CLEANING AND OXIDE ETCHING USING VAPOR-PHASE HYDROGEN-FLUORIDE

The vapor-phase hydrogen fluoride etch of oxides and nitride of silicon have been studied. A new mode of oxide selectivity, not possible with aqueous HF-based processes, gives rise to novel processes with practical applications. The inherent cleanliness and the resulting four to five times improvement in the electrical stress endurance of thin oxides make the vapor-phase process a viable substitute for the traditional processes based on aqueous HF.