A method to form a silicon oxide layer, where the method includes the step of providing a continuous flow of a silicon-containing precursor to a chamber housing a substrate, where the silicon-containing precursor is selected from TMOS, TEOS, OMTS, OMCTS, and TOMCATS. The method may also include the steps of providing a flow of an oxidizing precursor to the chamber, and causing a reaction between the silicon-containing precursor and the oxidizing precursor to form a silicon oxide layer. The method may further include varying over time a ratio of the silicon-containing precursor:oxidizing precursor flowed into the chamber to alter a rate of deposition of the silicon oxide on the substrate.