Methods of etching films with reduced surface roughness
AssigneeApplied Materials, Inc.
InventorsBenjamin Schmiege, Nitin K. Ingle, Srinivas D. Nemani, Jeffrey W. Anthis, Xikun Wang, Jie Liu, David Benjaminson
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Abstract
Provided are methods for etching films comprising transition metals which help to minimize higher etch rates at the grain boundaries of polycrystalline materials. Certain methods pertain to amorphization of the polycrystalline material, other pertain to plasma treatments, and yet other pertain to the use of small doses of halide transfer agents in the etch process.
Claims19
A method of etching a substrate, the method comprising:
- providing a polycrystalline film comprising a transition metal;
- amorphizing at least a portion of the polycrystalline film to provide an amorphous layer;
- exposing the amorphous layer to a halide transfer agent to provide an activated substrate surface;
- and
- exposing the activated substrate surface to a reagent comprising a Lewis base or pi acid to provide a vapor phase coordination complex comprising one or more atoms of the transition metal coordinated to one or more ligands from the reagent.
A method of etching a substrate, the method comprising:
- providing a polycrystalline film comprising a transition metal;
- exposing the polycrystalline film to an inert plasma, reducing gas or reagent vapor;
- exposing the polycrystalline film to a halide transfer agent to provide an activated substrate surface;
- and
- exposing the activated substrate surface to a reagent comprising a Lewis base or pi acid to provide a vapor phase coordination complex comprising one or more atoms of the transition metal coordinated to one or more ligands from the reagent.
A method of etching a substrate, the method comprising:
- activating a substrate surface comprising a polycrystalline film of a metal selected from the group consisting of Co, Cu, Ru, Ni, Fe, Pt, Mn and Pd, wherein activation of the substrate surface comprises exposing the substrate surface to Br2 or Cl2 to provide an activated substrate surface;
- and
- exposing the activated substrate surface to a reagent comprising TMEDA to provide a vapor phase coordination complex comprising one or more atoms of the Co, Cu, Ru, Ni, Fe, Pt, Mn or Pd coordinated to one or more ligands from the reagent,
- wherein the Br2 is present in an amount effective to etch about one Angstrom of the substrate surface.
Dependencies are inferred from the claim text.