TITANIUM OXIDE ETCH

摘要

Methods of selectively etching titanium oxide relative to silicon oxide, silicon nitride and/or other dielectrics are described. The methods include a remote plasma etch using plasma effluents formed from a fluorine-containing precursor and/or a chlorine-containing precursor. Plasma effluents from the remote plasma are flowed into a substrate processing region where the plasma effluents react with the titanium oxide. The plasmas effluents react with exposed surfaces and selectively remove titanium oxide while very slowly removing other exposed materials. A direction sputtering pretreatment is performed prior to the remote plasma etch and enables an increased selectivity as well as a directional selectivity. In some embodiments, the titanium oxide etch selectivity results partly from the presence of an ion suppression element positioned between the remote plasma and the substrate processing region.

主权项

1. A method of etching titanium oxide, the method comprising:
transferring a patterned substrate, having exposed regions of the titanium oxide, into a substrate processing region; flowing a pretreatment gas into a substrate processing region; forming a local pretreatment plasma in the substrate processing region and accelerating ionized components of the pretreatment gas into the titanium oxide; flowing a halogen-containing precursor into a remote plasma region fluidly coupled to a substrate processing region via through-holes in a showerhead while forming a remote plasma in the remote plasma region to produce plasma effluents; and etching the titanium oxide from a substrate disposed within the substrate processing region by flowing the plasma effluents into the substrate processing region through the through-holes in the showerhead.