A method of forming a
dielectric stack on a pre-treated surface. The method comprises pre-cleaning a
semiconductor wafer to remove native
oxide, such as by applying hydroflouric acid to form an HF-last surface, pre-treating the HF-last surface with ozonated deionized water, forming a
dielectric stack on the pre-treated surface and providing a flow of NH3 in a
process zone surrounding the
wafer. Alternately, the method includes pre-treating the HF-last surface with NH3, forming the stack after the pre-treating, and providing a flow of N2 in a
process zone surrounding the
wafer after the forming. The method also includes pre-treating the HF-last surface using an in-situ
steam generation process, forming the stack on the pre-treated surface, and annealing the wafer after the forming. The pre-treating includes providing an
inert gas flow in a
process zone surrounding the HF-last surface, reacting
hydrogen with an oxidizer in the process zone for a very
short duration, and providing an
inert gas flew in the process zone after the reacting.