Abstract: A method for etching metal silicide layers 22a, 22b and polysilicon layers 24a, 24b on a substrate 20 with high etching selectivity, and anisotropic etching properties, is described. In the method, the substrate 20 is placed in a plasma zone 55, and process gas comprising Cl.sub.2, O.sub.2, and N.sub.2, is introduced into the plasma zone. A plasma is formed from the process gas to selectively etch the metal silicide layer 22 at a first etch rate that is higher than a second rate of etching of the polysilicon layer 24, while providing substantially anisotropic etching of the metal silicide and polysilicon layers. Preferably, the plasma is formed using combined inductive and capacitive plasma sources.

Abstract: During the etching of a silicon-containing material using a halogen-containing etch gas, a silicon-hydride gas is added to the etch gas to provide increased sidewall protection during the etch. Suitably up to about 50 percent by volume of a silicon-containing gas such as silane is added to improve anisotropy of the etch and to prevent notching at the silicon-substrate interface.

Abstract: During the etching of a silicon-containing material using a halogen-containing etch gas, a silicon-hydride gas is added to the etch gas to provide increased sidewall protection during the etch. Suitably up to about 50 percent by volume of a silicon-containing gas such as silane is added to improve anisotropy of the etch and to prevent notching at the silicon-substrate interface.