Chambers, systems, and methods for electrochemically processing microfeature workpieces

A reactor for wet chemical processing of microfeature workpieces, the reactor comprising:

• a processing unit for providing a first processing fluid to a microfeature workpiece;
• an electrode unit including an electrode and being positined below the processing unit;
• a barrier unit having an upper portion mounted to a lower portion of the processing unit and a lower portion mounted to an upper portion of the electrode unit, the barrier unit including either a semipermeable cation-selective ion exchange barrier or a semipermeable anion-selective ion exchange barrier, and the barrier being releasably attached to the upper portion of the electrode unit by a quick-release mechanism having a latch;
• a first flow system for carrying the first processing fluid, the first flow system including a first portion in the processing unit, a second portion in the upper portion of the barrier unit in fluid communication with the first portion in the processing unit, and an external outlet at the upper portion of the barrier unit;
• and
• a second flow system for carrying a second processing fluid at least proximate to the electrode, the second flow system including a first portion in the electrode unit and a second portion in the lower portion of the barrier unit in fluid communication with the first portion in the electrode unit, wherein the ion exchange barrier separates the first processing fluid in the upper portion of the barrier unit from the second processing fluid in the lower portion of the barrier unit.