The present invention relates to methods of making oxide layers, preferably ultrathin oxide layers, with a high level of uniformity. One such method includes the steps of forming a substantially saturated or saturated oxide layer directly or indirectly on a semiconductor surface of a semiconductor substrate, and etchingly reducing the thickness of the substantially saturated or saturated oxide layer by an amount such that the etched oxide layer has a thickness less than the substantially saturated or saturated oxide layer. In certain embodiments, methods of the present invention provide etched oxide layers with a uniformity of less than about +/-10%. The present invention also relates to microelectronic devices including made by methods of the present invention and manufacturing systems for carrying out methods of the present invention.