Embodiments described herein generally provide a method for filling features formed on a substrate. In one embodiment, a method for selectively forming a silicon oxide layer on a substrate is provided. The method includes selectively depositing a silicon oxide layer within a patterned feature formed on a surface of a substrate, wherein the patterned feature comprises one or more sidewalls and a deposition surface at a bottom of the patterned feature, the one or more sidewalls comprise a silicon oxide, a silicon nitride, or a combination thereof, the deposition surface essentially consists of silicon, and the selectively deposited silicon oxide layer is formed on the deposition surface by flowing tetraethyl orthosilicate (TEOS) and ozone over the patterned feature.