Patent ID: 7842158

Claim:
A carrier head for chemical mechanical polishing of a substrate, comprising: a base; and a flexible membrane extending beneath the base, wherein the flexible membrane includes a central portion with an outer surface to provide a substrate receiving surface, a perimeter portion connecting the central portion to the base, and at least one flap extending from an inner surface of the central portion and connected to the base, the flap dividing the central portion into a plurality of regions and dividing a volume between flexible membrane and the base into a plurality of chambers, each of the plurality of chambers bounded by the inner surface of an associated region of the plurality of regions so that the plurality of chambers provide independently adjustable pressures to the substrate receiving surface in the plurality of regions, and wherein the flap includes a laterally extending first section and an angled second section extending beneath the laterally extending first section and connecting the laterally extending first section to the central portion, and wherein the angled second section is more rigid than the laterally extending first section.