Chemical mechanical polishing of a metal layer with polishing rate monitoring
AssigneeApplied Materials, Inc.
InventorsFred C. Redeker, Rajeev Bajaj
Life of this patent
Estimating the term…
Abstract
A method of chemical mechanical polishing a metal layer on a substrate in which the substrate is polished at a first polishing rate. Polishing is monitored with an eddy current monitoring system, and the polishing rate is reduced to a second polishing rate when the eddy current monitoring system indicates that a predetermined thickness of the metal layer remains on the substrate. Then polishing is monitored with an optical monitoring system, and polishing is halted when the optical monitoring system indicates that an underlying layer is at least partially exposed.
Claims14
A method of chemical mechanical polishing a metal layer on a substrate, comprising:
- polishing the metal layer on the substrate at a first polishing station with a first polishing surface at a first polishing rate;
- monitoring polishing at the first polishing station with an eddy current monitoring system;
- transferring the substrate to a second polishing station when the eddy current monitoring system indicates that a predetermined thickness of the metal layer remains on the substrate;
- polishing the metal layer on the substrate at the second polishing station with a second polishing surface at a second polishing rate that is lower than the first polishing rate;
- monitoring polishing of the metal layer at the second polishing station with an optical monitoring system;
- and
- halting polishing when the optical monitoring system indicates that a first underlying layer is at least partially exposed.
A method of chemical mechanical polishing a metal layer on a substrate, comprising:
- polishing the metal layer on the substrate at a first polishing station with a first polishing surface at a first polishing rate;
- monitoring polishing at the first polishing station with an eddy current monitoring system;
- reducing the polishing rate at the first polishing station when the eddy current monitoring system indicates that a predetermined thickness of the metal layer remains on the substrate;
- monitoring polishing of the metal layer at the first polishing station with an optical monitoring system;
- and
- halting polishing when the optical monitoring system indicates that a first underlying layer is at least partially exposed.
A method of chemical mechanical polishing a metal layer on a substrate, comprising:
- polishing the metal layer on the substrate at a first polishing rate;
- monitoring polishing with an eddy current monitoring system;
- reducing the polishing rate when the eddy current monitoring system indicates that a predetermined thickness of the metal layer remains on the substrate;
- monitoring polishing of the metal layer with an optical monitoring system;
- and
- halting polishing when the optical monitoring system indicates that an underlying layer is at least partially exposed.
Dependencies are inferred from the claim text.