Chucking warped wafer with bellows

A vacuum chuck comprising:

• a body defining a chucking surface and having a suction assembly opening defined by the chucking surface;
• a suction assembly disposed in the suction assembly opening, wherein the suction assembly comprises:
• a base;
• a bellows having a first end and a second end opposite the first end, wherein the second end of the bellows is disposed on the base;
• a pad having a first surface and a second surface opposite the first surface, wherein the second surface of the pad is disposed on the first end of the bellows, wherein the first surface defines a recess in the pad, the pad further comprising at least one channel between the first surface and second surface, the channel being defined by a channel wall;
• a vacuum port in fluid communication with a first volume and a second volume, wherein the first volume is defined by the base, the bellows, and the pad, and wherein the second volume is defined partly by the recess;
• and
• a spring inside the bellows disposed between the base and the pad;
• wherein the first surface of the pad is a distance from the chucking surface in a first position and the first surface of the pad is more proximate the chucking surface in a second position than in the first position.