A system for generating an output image is provided. The semiconductor substrate includes a substrate body having at least an opening formed on a surface thereof, wherein the surface of the substrate body and a wall of the opening are made of an insulating material; and a circuit layer formed on the surface of the substrate body, wherein the circuit layer covers an end of the opening and is electrically insulated from the opening. The remote database contains second information regarding the purchase of each token. The PAC rich concentrate is recirculated to the contacting zone to increase the concentration of PAC in the contacting zone.