Etching processes and processing assemblies

Abstract

The current disclosure relates to methods of selectively etching material from a first surface of a substrate relative to a second surface of the substrate. The method includes providing the substrate having a first surface comprising an etchable material, and a second surface comprising a non-etchable material in a reaction chamber, providing hydrogen-containing plasma into the reaction chamber to reduce the etchable material to a predetermined depth; and providing remotely-generated reactive halogen species and hydrogen into the reaction chamber to selectively etch the reduced etchable material. The disclosure further relates to methods of selectively etching at least two different etchable materials simultaneously from a surface of a substrate relative to a non-etchable material on the same substrate, to methods of simultaneous differential etching of three or more etchable materials on a substrate, as well as to assemblies for processing semiconductor substrates.