| abstract |
According to the present invention, titanium nitride is removed from a substrate having titanium nitride, tungsten, and a low dielectric constant interlayer insulating film without corroding tungsten and the low dielectric constant interlayer insulating film, (A) an oxidizing agent that is at least one selected from the group consisting of potassium permanganate, ammonium peroxodisulfate, potassium peroxodisulfate, and sodium peroxodisulfate, (B) a fluorine compound, and (C) a tungsten anticorrosive And a liquid composition having a pH value of 0 to 4, The (C) tungsten anticorrosive contains two or more different compounds selected from the C1 compound group consisting of alkylamine and its salt, fluoroalkylamine and its salt, or is selected from the C1 compound group One or more selected from C2 compound group consisting of polyoxyalkylene alkylamine, polyoxyalkylene fluoroalkylamine and the like, The liquid composition in which the concentration of potassium permanganate in the (A) oxidizing agent is 0.001 to 0.1% by mass, and the concentration of the (B) fluorine compound is 0.01 to 1% by mass. Can be provided. |