Electronic grade phosphoric acid belongs to high-purity phosphoric acid and is a widely used ultra-high purity chemical reagent in the electronics industry. It is mainly used for wet cleaning and wet etching of chips, including cleaning before substrate coating, etching and final debonding during photolithography, as well as cleaning and insulation film etching during the production process of silicon wafers, semiconductor film etching, conductor film etching, organic material etching, etc. Inorganic anions in phosphoric acid may cause circuit noise damage, Therefore, it is necessary to use a content analyzer, as ion chromatography has unique advantages in determining inorganic anions.