Patent ID: 9613822
Date: 2017-04-04
CPC Classifications: H01J,H01L

Claim:
1. A method of etching a patterned substrate, the method comprising: placing the patterned substrate in a substrate processing region of a substrate processing chamber, wherein the patterned substrate comprises an exposed silicon oxide portion and an exposed silicon nitride portion; flowing a fluorine-containing precursor and an oxygen-containing precursor into a remote plasma region fluidly coupled to the substrate processing region while forming a remote plasma in the remote plasma region to produce plasma effluents; flowing a hydrogen-and-oxygen-containing precursor into the substrate processing region without first passing the hydrogen-and-oxygen-containing precursor through the remote plasma region, wherein the hydrogen-and-oxygen-containing precursor comprises an O—H bond; and etching the exposed silicon oxide portion by flowing the plasma effluents into the substrate processing region, wherein the exposed silicon oxide portion etches at a first etch rate and the exposed silicon nitride portion etches at a second etch rate which is lower than the first etch rate.