ETCHING SOLUTION AND TRENCH ISOLATION STRUCTURE-FORMATION PROCESS EMPOLYING THE SAME

摘要

The present invention provides an etching solution less affected by trench structures and also provides an isolation structure-formation process employing the solution. The etching solution contains hydrofluoric acid and an organic solvent. The organic solvent has aδH value defined by Hansen solubility parameters in the range of 4 to 12 inclusive and the saturation solubility thereof in water is 5 wt % or more at 20° C. This solution can be adopted instead of known etching solutions used in conventional production processes of semiconductor elements.