SOLUBLE SURFACTANT ADDITIVES FOR AMMONIUM FLUORIDE/HYDROFLUORIC ACID OXIDE ETCHANT SOLUTIONS

摘要

SOLUBLE SURFACTANT ADDITIVES FOR AMMONIUM FLUORIDE/HYDROFLUORIC ACID OXIDE ETCHANT SOLUTIONS Silicon trioxide etching solutions with soluble surfact additives are provided. The improved silicon dioxide etchants are produced by adding soluble perfluronated surfactant additives to standard oxide etchants in the manufacture of integrated circuits. These surfactant additives are unique because they remain dissolved in the oxide etchant (ammonium fluoride/hydrofluoric acid mixture) even after 0.2 micron filtration. In addition, the filtered solutions retain their surface active properties and are low in metallic ion impurities. The surfactant additives provide etchant solutions with lower surface tensions, which improves substrate wetting and yields better etchant performance. The surfactant does not leave residues or adversely affect etchant profiles.