Combination, method, and composition for chemical mechanical planarization of a tungsten-containing substrate
AssigneeAir Products and Chemicals, Inc.
InventorsDianne Rachel McConnell, Ann Marie Hurst
Life of this patent
Estimating the term…
Abstract
A combination, composition and associated method for chemical mechanical planarization of a tungsten-containing substrate are described herein which afford tunability of tungsten/dielectric selectivity and low selectivity for tungsten removal in relation to dielectric material. Removal rates for both tungsten and dielectric are high and stability of the slurry (e.g., with respect to pH drift over time) is high.
Claims8
A combination of a chemical mechanical polishing composition in contact with a substrate surface having at least one feature thereon comprising tungsten and at least one feature thereon comprising a dielectric material, said combination comprising:
- a substrate comprising submicron integrated circuits and having a surface having at least one feature thereon comprising tungsten, said substrate surface contacting a chemical mechanical polishing composition comprising;
- a)periodic acid;
- b)an abrasive;
- c) an amino-alcohol compound
- wherein
- said periodic acid and said abrasive are present in a combined amount sufficient to render the substrate surface substantially planar and to maintain a removal rate of tungsten of at least 800 Angstroms per minute upon chemical-mechanical polishing thereof when polishing is done at 4 psi of down force;
- and
- a tunable tungsten/dielectric selectivity ranging from 0.5 to 1.5 is realized upon chemical-mechanical polishing the substrate using the composition.
Dependencies are inferred from the claim text.