Regeneration process of etching solution, etching process, and etching system

摘要

An etching solution comprising phosphoric acid is regenerated by taking the etching solution out of an etch bath. The etching solution contains a silicon compound formed by etching. Water is added to the taken-out etching solution to lower phosphoric acid to 80-50 wt.%. The silicon compound is removed, which has precipitated in the etching solution by the lowering of the concentration of phosphoric acid, from the etching solution. An independent claim is also included for an etching system for the inventive etching process comprising a dilution and precipitation unit (4) for taking the etching solution out of the etch bath (1), and diluting the taken-out etching solution with water to precipitate the silicon compound. A filtration unit (6) is provided for the silicon compound, and concentration unit (7) or heating unit is provided for the etching solution.