Provided are an anionic surfactant-containing
etching solution for removal of an
oxide film, preparation methods thereof, and methods of fabricating a
semiconductor device using the
etching solution. The
etching solution includes a
hydrofluoric acid (HF), deionized water, and an anionic surfactant. The anionic surfactant is a compound in which an
anime salt is added as a counter
ion, as represented by R1—OSO3−HA+, R1—CO2−HA+, R1—PO42−(HA+)2, (R1)2—PO4−HA+, or R1—SO3−HA+ where R1 is a straight or branched
hydrocarbon group of C4 to C22 and A is
ammonia or amine. The etching solution provides a high
etching selectivity ratio of an
oxide film to a
nitride film or a polysilicon film. Therefore, in a
semiconductor device fabrication process such as a STI device isolation process or a
capacitor formation process, when an
oxide film is exposed together with a
nitride film or a polysilicon film, the etching solution can be efficiently used in selectively removing only the oxide film.