PHOSPHORIC ACID ETCHING BATH HAVING DUAL PIPE SYSTEM FOR SUPPLYING DEIONIZED WATER

摘要

PURPOSE: A phosphoric acid etching bath having a dual pipe system for supplying deionized water is provided to minimize the damage and perform stably a process in a wet station by reducing the shock due to an explosive reaction between deionized water and phosphoric acid solution. CONSTITUTION: A phosphoric acid etching bath having a deionized water supply system of a dual pipe structure includes an internal etching bath(112), an external chemical receptacle(114), and a deionized water supply system. The internal etching bath(112) is used for storing phosphoric acid solution. The external chemical receptacle(114) is formed around the internal etching bath in order to store chemical solution supplied to the internal etching bath. The deionized water supply system includes a first supply line(120) and a second supply line(130). The first supply pipe(120) is used for supplying the deionized water to the external chemical receptacle. The second supply pipe(130) includes a plurality of fine holes to disperse the deionized water to the inside of the external chemical receptacle.