Abstract: In a tantalum oxide film removal method and apparatus, a silicon substrate having a tantalum oxide film is supported on a spin chuck. A mixed aqueous solution including hydrofluoric acid and organic acid is supplied to the silicon substrate while rotating the silicon substrate together with the spin chuck. The mixed aqueous solution comes into contact with the tantalum oxide film existing on the silicon substrate to remove the tantalum oxide film by the chemical reaction therebetween.

Abstract: In a titanium oxide film removal method and apparatus, a silicon substrate having the titanium oxide film is supported on a spin chuck. A first mixed aqueous solution including hydrofluoric acid and non-oxidizing acid or a second mixed aqueous solution including hydrofluoric acid and organic acid is supplied to the silicon substrate while rotating the silicon substrate together with the spin chuk. The first or the second aqueous solution comes into contact with the titanium oxide film existing on the silicon substrate to remove the titanium oxide film by a reaction between the first or the second mixed aqueous solution and the titanium oxide film.