A GAS-PHASE CHEMICAL ETCHANT FOR BORON-NITRIDE FILMS

We have demonstrated that boron nitride films deposited on silicon and tantalum can be etched in a hot filament environment with an input ga s composition of 1% methane in hydrogen. Etching experiments were carr ied out at around 800 K on a tantalum foil and at somewhat higher temp eratures on silicon substrates. If the etchant is atomic hydrogen or m ethyl radical, then we estimate etching efficiencies (atoms etched per collision) of similar to 10(-5) or 10(-4) for these species, respecti vely. (C) 1995 American Institute of Physics.