US Patent 7202166 Surface preparation prior to deposition on germanium

Methods are provided for treating germanium surfaces in preparation for subsequent deposition, particularly gate dielectric deposition by atomic layer deposition (ALD). Prior to depositing, the germanium surface is treated with plasma products or thermally reacted with vapor reactants. Examples of surface treatments leave oxygen bridges, nitrogen bridges, —OH, —NH and/or —NH2 terminations that more readily adsorb ALD reactants. The surface treatments avoid deep penetration of the reactants into the germanium bulk but improve nucleation.