A system for lithography patterning includes a first supply pipe for supplying a first solution, a second supply pipe for supplying a second solution, and a third supply pipe coupled to the first and second supply pipes for receiving the first and second solutions respectively and mixing the first and second solutions into a mixture. The third supply pipe couples to the first and second supply pipe at a junction. At the junction the first solution in the first supply pipe flows in a direction opposite to that of the second solution in the second supply pipe. The system further includes a first control unit coupled to the first supply pipe and configured to control a flow rate of the first solution, and a second control unit coupled to the second supply pipe and configured to control a flow rate of the second solution.