Methods of fabricating an oxide layer on a semiconductor substrate are provided herein. The oxide layer may be formed over an entire structure disposed on the substrate, or selectively formed on a non-metal containing layer with little or no oxidation of an exposed metal-containing layer. The methods disclosed herein may be performed in a variety of process chambers, including but not limited to decoupled plasma oxidation chambers, rapid and/or remote plasma oxidation chambers, and/or plasma immersion ion implantation chambers. In some embodiments, a method may include providing a substrate comprising a metal-containing layer and non-metal containing layer; and forming an oxide layer on an exposed surface of the non-metal containing layer by exposing the substrate to a plasma formed from a process gas comprising a hydrogen-containing gas, an oxygen-containing gas, and at least one of a supplemental oxygen-containing gas or a nitrogen-containing gas.