The invention relates to the technical field of
etching solutions, and particularly discloses a buffer
oxide etching solution with long
etching life and application, the etching solution contains
hydrofluoric acid,
ammonium fluoride, an additive and an inhibitor; wherein the additive is fluorinated
fatty alcohol; the inhibitor is
polyol. The etching solution disclosed by the invention is used for cleaning and etching a
silicon oxide film layer in
semiconductor manufacturing. Due to heat release in the etching process and long-time contact with the atmospheric environment, water is volatilized, meanwhile, gaseous
hydrofluoric acid causes large change of the concentration of the liquid
medicine, a multi-molecular, compact and non-volatile film is formed on the surface of the liquid
medicine through the added additive, water molecules are physically prevented from escaping into air, meanwhile, the inhibitor binds the water molecules through polar groups, and the
corrosion resistance of the liquid
medicine is improved. And the
diffusion activity is inhibited, so that the etching solution is small in
moisture loss after long-time etching, and the concentration of
hydrofluoric acid is more stable, thereby obtaining a longer etching life.