Patent ID: 9093390
Filing Date: 2015-07-28
Classification: B44C,C03C,C09K,H01J,H01L

Abstract:
1. A method of etching silicon oxide from the walls of a trench on a surface of a patterned substrate in a substrate processing chamber, the chamber having a substrate processing region and a plasma generating region remote from the substrate processing region, the method comprising: exposing the patterned substrate to hydrogen by flowing a hydrogen-containing precursor into the substrate processing region, removing process effluents including unadsorbed hydrogen-containing precursor from the substrate processing region, exposing the patterned substrate to hydrogen-free fluorine by flowing a fluorine-containing precursor into the substrate processing region to form solid by-products on the patterned substrate, and removing process effluents including unreacted fluorine-containing precursor from the substrate processing region; and raising a temperature of the substrate above a sublimation temperature to remove the solid by-products, wherein the sublimation operation occurs after the step of exposing the patterned substrate to fluorine, and wherein the at least four sequential steps in combination with the sublimation operation are referred to collectively as an etch cycle.