Methods of fabricating an oxide layer on a semiconductor substrate are provided herein. In some embodiments, a method of forming an oxide layer on a semiconductor substrate includes placing a substrate to be oxidized on a substrate support in a vacuum chamber of a plasma reactor, the chamber having an ion generation region remote from the substrate support; introducing a process gas into the chamber, the process gas comprising at least one of hydrogen (H2) and oxygen (O2)—provided at a flow rate ratio of hydrogen (H2) to oxygen (O2) of up to about 3:1—or water vapor (H2O vapor); and generating an inductively coupled plasma in the ion generation region of the chamber to form a silicon oxide layer on the substrate.