Method Of Reducing The Surface Tension Of Buffered Hydrofluoric Acid By Adding Isopropanol
Original Publication Date: 1979-Aug-01
Included in the Prior Art Database: 2005-Feb-20
Previously, several surface active substances, such as FC-98 (a fluorochemical surfactant by 3M Corporation) with a concentration of 0.14 per cent by volume, were used to improve the etching of SiO(2) by means of 7:1 buffered hydrofluoric acid. In spite of this relatively high quantity of wetting agents, the reductions obtained in the surface tension were very small, since the high salt concentration of the buffered hydrofluoric acid causes the wetting agents to be salted out.