Patent ID: 8871032

Claim:
A semiconductor apparatus, comprising: a first tank configured to accommodate a first fluid; a second tank adjacent to the first tank and configured to accommodate a second fluid; a cycling system configured between the first tank and the second tank, the cycling system including at least one first conduit, the at least one first conduit having an end substantially below a top surface and near a bottom surface of the second fluid within the second tank; a fluid providing system being exclusive of the first tank, fluidly coupled to the second tank and configured to provide the second fluid into the second tank, the fluid providing system including at least one second conduit with a delivery end substantially below the top surface and at a lower location near the bottom surface of the second tank and an inlet end coupled to the fluid providing system, the second tank positioned to receive overflow directly from the first tank at an upper location above the lower location; an overflow system coupled to the second tank and configured to remove the second fluid when the top surface of the second fluid is substantially equal to or higher than a pre-determined level; a storage medium configured to store a number of substrates to be processed within the first tank; and a processor coupled to the fluid providing system and the storage medium, the processor configured to generate a signal corresponding to the number of the substrates based on a formula to control a flow rate of the second fluid flowing into the second tank and therefore a removal rate of a material formed on said substrates.