US 2026/0305264 A1 · POLISHING METHOD AND POLISHING APPARATUS

Abstract

A technique capable of stabilizing pressure control of a polishing head when a polishing rate changes significantly during polishing of a workpiece, such as a wafer, is disclosed. A polishing method includes during polishing of the workpiece, calculating a plurality of polishing rates of a plurality of regions within the surface of the workpiece; and detecting a plurality of change points of the plurality of polishing rates. Before the plurality of change points of the plurality of polishing rates are detected, the polishing head performs a polishing-amount control operation of polishing the plurality of regions of the workpiece by the same polishing amount. After the plurality of change points of the plurality of polishing rates are detected, the polishing head performs a profile control operation of polishing the plurality of regions of the workpiece such that a film-thickness profile of the workpiece reaches a target film-thickness profile.

Claims12

Dependent claims

A polishing method comprising:

polishing a workpiece by pressing a surface of the workpiece against a polishing pad with a plurality of pressure chambers of a polishing head while measuring a film thickness of the workpiece;
during polishing of the workpiece, calculating a plurality of polishing rates of a plurality of regions within the surface of the workpiece;
and
detecting a plurality of change points of the plurality of polishing rates,
wherein, before the plurality of change points of the plurality of polishing rates are detected, the polishing head performs a polishing-amount control operation of polishing the plurality of regions of the workpiece by the same polishing amount, and
wherein, after the plurality of change points of the plurality of polishing rates are detected, the polishing head performs a profile control operation of polishing the plurality of regions of the workpiece such that a film-thickness profile of the workpiece reaches a target film-thickness profile.

3 more elements

A polishing apparatus comprising:

a polishing table configured to support a polishing pad;
a polishing head having a plurality of pressure chambers configured to press a surface of a workpiece against the polishing pad;
a film-thickness sensor configured to measure a film thickness of the workpiece;
a pressure regulating device configured to regulate pressures in the plurality of pressure chambers;
and
a polishing controller configured to perform pressure control of the polishing head by controlling operation of the pressure regulating device,
wherein the polishing controller is configured to:
calculate a plurality of polishing rates of a plurality of regions within the surface of the workpiece;
detect a plurality of change points of the plurality of polishing rates;
before detecting the plurality of change points of the plurality of polishing rates, instruct the pressure regulating device to cause the polishing head to perform a polishing-amount control operation of polishing the plurality of regions of the workpiece by the same polishing amount;
and
after detecting the plurality of change points of the plurality of polishing rates, instruct the pressure regulating device to cause the polishing head to perform a profile control operation of polishing the plurality of regions of the workpiece such that a film-thickness profile of the workpiece reaches a target film-thickness profile.

9 more elements

Dependencies are inferred from the claim text.

Polishing method and polishing apparatus

Life of this patent

Polishing method and polishing apparatus

Life of this patent

Abstract

Claims12