Methods, apparatuses, and systems related to trim a semiconductor structure using oxygen are described. An example method includes forming a support structure for a semiconductor structure having a first silicate material on a working surface. The method further includes forming a first nitride material on the first silicate material. The method further includes forming a second silicate material on the first nitride material. The method further includes forming a second nitride material on the second silicate material. The method further includes forming an opening through the semiconductor structure. The method further includes depositing an electrode material within the opening. The method further includes removing portions of the support structure. The method further includes performing a controlled oxidative trim to an upper portion of the electrode material.