Workpiece carrier with adjustable pressure zones and barriers

An improved wafer carrier, for carrying a wafer having opposed active and rear surfaces, a central portion and an outer periphery, the carrier comprising:

• a resilient bladder having opposed working and rear surfaces, a central portion and an outer periphery;
• an internal support structure including a working face and an outer periphery which supports the resilient bladder, wherein the working face includes at least one groove recessed therein;
• and
• a pressure regulator configured to selectively supply negative and positive pressure to the rear surface of the resilient bladder
• wherein the resilient bladder deforms into the at least one groove of the internal support structure to create at least one channel recessed in the working surface of the resilient bladder extending from an inner portion of the resilient bladder to the outer periphery of the resilient bladder, when the pressure regulator supplies negative pressure to the rear surface of the bladder.