Method and composition for polishing a substrate
AssigneeApplied Materials, Inc.
InventorsRenhe Jia, Feng Q. Liu, Stan D. Tsai, Liang-Yuh Chen
Life of this patent
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Abstract
Polishing compositions and methods for removing conductive materials and barrier materials from a substrate surface are provided. Polishing compositions are provided for removing at least a barrier material from a substrate surface by a chemical mechanical polishing process or by an electrochemical mechanical polishing process. The polishing compositions used in barrier removal may further be used after a process for electrochemical mechanical planarization process of a conductive material. The polishing compositions and methods described herein improve the effective removal rate of materials from the substrate surface with a reduction in planarization type defects.
Claims14
A method of processing a substrate, comprising:
- disposing a substrate having patterned feature definitions, a barrier material disposed in the patterned feature definitions, and a tungsten layer formed thereon in a polishing apparatus;
- polishing the tungsten layer to expose the barrier layer;
- polishing the barrier layer by a process comprising:
- providing a barrier polishing composition comprising:
- between about 1 wt. % and about 10 wt. % of an oxidizer;
- between about 0.5 wt. % and about 5 wt. % of a chelating agent;
- between about 0.0001 wt % and about 1 wt % of a polymeric stabilizer;
- between about 0.3 wt % and about 10 wt % of abrasive particles;
- a pH between about 1 and about 6;
- and
- a solvent;
- and
- contacting the substrate to a polishing article;
- providing relative motion between the substrate and the polishing article;
- and
- removing the barrier material from the substrate, wherein the barrier layer is removed at a barrier layer removal rate to tungsten removal rate between about 30:1 and about 80:1.
A method of processing a substrate comprising:
- disposing a substrate having patterned feature definitions, a barrier material disposed in the patterned feature definitions, and a tungsten layer formed thereon in a polishing apparatus having at least one electrochemical mechanical polishing station;
- polishing the tungsten layer to expose the barrier layer, wherein polishing the tungsten layer comprises;
- polishing the substrate in the at least one electrochemical mechanical polishing station to remove a first portion of the tungsten layer by a process comprising:
- providing a first polishing composition between the first electrode and the substrate;
- contacting the substrate to a polishing article at a first pressure between the substrate and the polishing article;
- providing a first relative motion between the substrate and the polishing article;
- and
- applying a first bias between the first electrode and the second electrode;
- and
- polishing the substrate in the at least one electrochemical mechanical polishing station to remove a second portion of the tungsten layer by a process comprising:
- providing a second polishing composition between the first electrode and the substrate;
- contacting the substrate to a polishing article at a second pressure between the substrate and the polishing article;
- providing a second relative motion between the substrate and the polishing article;
- and
- applying a second bias between the first electrode and the second electrode;
- polishing the barrier layer by a process comprising:
- providing a barrier polishing composition comprising:
- between about 1 wt. % and about 10 wt. % of an oxidizer;
- between about 0.5 wt. % and about 5 wt. % of a chelating agent;
- between about 0.0001 wt % and about 1 wt % of a polymeric stabilizer;
- between about 0.3 wt % and about 10 wt % of abrasive particles;
- a pH between about 1 and about 6;
- and
- a solvent;
- and
- contacting the substrate to a polishing article;
- providing relative motion between the substrate and the polishing article;
- and
- removing the barrier material from the substrate.
A method of processing a substrate comprising a dielectric surface, feature definitions formed in the dielectric surface, a barrier material disposed in the feature definitions and on the dielectric surface, and a conductive material disposed on the barrier material, the method comprising:
- polishing the conductive material to expose the barrier material;
- disposing the substrate in a process apparatus comprising a first electrode and a second electrode, wherein the substrate is in electrical contact with the second electrode;
- providing a polishing composition between the first electrode and the substrate, wherein the polishing composition comprises:
- an acid based electrolyte system;
- one or more etching agents;
- one or more etching inhibitors, wherein the one or more etching inhibitors are selected from the group consisting of polymethylacrylic acids, polycarboxylic acid, polyphosphate, and combinations thereof;
- one or more activating agents;
- one or more pH adjusting agents to provide a pH between about 2 and about 7;
- and
- a solvent;
- applying a pressure between the substrate and a polishing article by use of a polishing head;
- providing relative motion between the substrate and the polishing article by mechanical means;
- applying a bias between the first electrode and the second electrode;
- and
- removing barrier material from the dielectric surface.
A method of processing a substrate comprising a dielectric surface, feature definitions formed in the dielectric surface, a barrier material disposed in the feature definitions and the dielectric surface, and a conductive material disposed on the barrier material, the method comprising:
- polishing the conductive material to expose the barrier material;
- disposing the substrate in a process apparatus comprising a first electrode and a second electrode, wherein the substrate is in electrical contact with the second electrode;
- providing a polishing composition between the first electrode and the substrate, wherein the polishing composition comprises;
- an acid based electrolyte system;
- one or more etching agents;
- one or more etching inhibitors;
- one or more activating agents, wherein the activating agents are selected from the group of iron compounds, aluminum compounds, hexafluorotitanium ([TiF6]2−) salts, hexafluorosilicon ([SiF6]2−), and combinations thereof;
- one or more pH adjusting agents to provide a pH between about 2 and about 7;
- and
- a solvent;
- applying a pressure between the substrate and a polishing article by use of a polishing head;
- providing relative motion between the substrate and the polishing article by mechanical means;
- applying a bias between the first electrode and the second electrode;
- and
- removing barrier material from the dielectric surface.
Dependencies are inferred from the claim text.