US 2004/0069406 A1 · CMP apparatus polishing head with concentric pressure zones

Abstract

A CMP polishing head having multiple concentric pressure zones for selectively increasing polishing pressure against selected regions of a semiconductor wafer in order to compensate for variations in polishing rates on the wafer surface otherwise caused by ridges or other non-uniformities in the wafer surface. The polishing head of the present invention comprises multiple, concentric, inflatable pressure rings each of which may be selectively inflated to increase the polishing pressure against a concentric ridge or material elevation on the corresponding concentric region of the wafer surface and increase the polishing rate of the concentric ridge or elevation between the rotating polishing head and a stationary polishing pad. A channel selector may be included in the polishing head for selectively aligning an air/pressure vacuum source with a selected one of multiple pressure tubes that connect to the respective pressure rings.

Claims20

Dependent claims

A polishing head for polishing a substrate on a polishing apparatus, comprising:

a housing for mounting on the apparatus;
a support plate carried by said housing;
a flexible membrane carried by said housing;
and
at least three substantially concentric pressure rings carried by said support plate for inflation against said flexible membrane and pressing said flexible membrane against the substrate to increase a polishing rate of selected regions on the substrate.

2 more elements

A polishing head for polishing a substrate on a polishing apparatus, comprising:

a housing for mounting on the apparatus;
a support plate carried by said housing;
a flexible membrane carried by said housing;
at least three substantially concentric pressure rings carried by said support plate for inflation against said flexible membrane and pressing said flexible membrane against the substrate to increase a polishing rate of selected regions on the substrate;
and
a channel selector comprising a casing carried by said housing, a duct roller having a duct rotatably mounted in said casing for fluid communication of said duct with a selected one of said at least three pressure rings for reversibly inflating said selected one of said at least three pressure rings, and a duct roller rotating mechanism for rotating said duct roller in said casing.

3 more elements

Dependencies are inferred from the claim text.

CMP apparatus polishing head with concentric pressure zones

Life of this patent

CMP apparatus polishing head with concentric pressure zones

Life of this patent

Abstract

Claims20