APPARATUS AND METHOD FOR AUTOMATICALLY REPLENISHING HYDROFLUORIC ACID SOLUTION TANK WITH HYDROFLUORIC ACID SOLUTION

摘要

PURPOSE: An apparatus and a method for replenishing automatically a hydrofluoric acid solution are provided to maintain constantly the amount of the hydrofluoric acid solution by detecting the amount of the hydrofluoric acid solution remaining inside a hydrofluoric acid solution tank. CONSTITUTION: A hydrofluoric acid solution tank(110) is coupled to a hydrofluoric acid solution supply line having an electronic switching valve and a manual switching valve, a nitrogen gas supply line, and a hydrofluoric acid gas exhaust line. A hydrofluoric acid solution residue sensor is installed at a lower part of an inside of the hydrofluoric acid solution tank in order to sense the remaining hydrofluoric acid solution and generate a predetermined electric signal. A controller(140) is used for receiving an electric signal from the hydrofluoric acid solution residue sensor and outputting an electric signal to replenish the hydrofluoric acid solution. An actuator(160) is used for opening the electronic switching valve according to the output signal of the controller.