US 6,958,277 B2 · Surface preparation prior to deposition

Abstract

Methods are provided herein for treating substrate surfaces in preparation for subsequent nucleation-sensitive depositions (e.g., polysilicon or poly-SiGe) and adsorption-driven deposition (e.g. atomic layer deposition or ALD). Prior to depositing, the surface is treated with non-depositing plasma products. The treated surface more readily nucleates polysilicon and poly-SiGe (such as for a gate electrode), or more readily adsorbs ALD reactants (such as for a gate dielectric). The surface treatment provides surface moieties more readily susceptible to a subsequent deposition reaction, or more readily susceptible to further surface treatment prior to deposition. By changing the surface termination of the substrate with a low temperature radical treatment, subsequent deposition is advantageously facilitated without depositing a layer of any appreciable thickness and without significantly affecting the bulk properties of the underlying material. Preferably less than 10 Å of the bulk material incorporates the excited species, which can include fluorine, chlorine and particularly nitrogen excited species.

Claims15

Dependent claims

A method of forming a transistor gate stack, the method comprising:

forming a gate dielectric over a semiconductor substrate;
exposing the gate dielectric to a source of nitrogen excited species, wherein exposing incorporates less than about 10 atomic % nitrogen at a depth of greater than about 10 Å from an upper surface of the gate dielectric;
and
depositing a silicon-containing gate electrode over the gate dielectric after exposing the gate dielectric to the source of nitrogen excited species, wherein the gate electrode contacts a portion of the pate dielectric exposed to the source of nitrogen excited species.

1 more element

Dependencies are inferred from the claim text.

Surface preparation prior to deposition

Life of this patent

Surface preparation prior to deposition

Life of this patent

Abstract

Claims15