REGENERATING METHOD OF PHOTORESIST DEVELOPER WASTE LIQUID

摘要

PROBLEM TO BE SOLVED: To provide an easy and efficient regenerating method of a developer waste liquid of a photoresist. SOLUTION: In this method to treat a developer waste liquid of a photoresist essentially containing a photoresist and tetraalkyl ammonium (TAA) ion, at least a process to concentrate TAA ion by electrodialysis and/or electrolysis and a process to adsorb and remove impurities by bringing the liquid into contact with an ion exchange resin are carried out. The ion exchange resin is preferably an anion exchange resin and a hydrogen ion type (H-type) and/or TAA ion type (TAA) cation exchange resin. The impurities are residual photoresist, other anion component and cation component such as Na<+> . Thereby, a soln. of tetraalkyl ammonium hydroxide of high purity which can be reused as a photoresist developer is regenerated and recovered from the developer waste liquid of a photoresist.