An oxidation process that produces multi-layer, yet very thin oxides of silicon, formed on silicon substrates, includes pushing wafers at a particular range of speeds, into a furnace at a particular range of temperatures, sequentially oxidizing the wafers in varying chemical ambients, and operating an external chlorine compound generator coupled to the furnace. Oxides formed in this manner have good uniformity and low interface state density and are suitable for forming FETs. In a particular embodiment, a first portion of an oxide stack is formed in an oxygen/nitrogen ambient, a second portion of an oxide stack is formed in a carbon dioxide/hydrogen chloride/oxygen ambient, and a third portion of an oxide stack is formed by a wet oxidation. The second portion of the oxide stack is formed when 1,2-dichloroethylene is treated with heat and oxygen to produce carbon dioxide and hydrogen chloride gas that is then introduced into the furnace.