Abstract: This invention is concerning an etchant composition used to etch a silicon-containing film formed on a target substrate. The etchant composition includes at least one selected from the group consisting of an organic compound containing a hydroxyl group, an organic compound containing a carbonyl group, an inorganic acid and inorganic salt, hydrofluoric acid, ammonium fluoride and an organic acid.

Abstract: This invention is concerning an etchant composition used to etch a silicon-containing film formed on a target substrate. The etchant composition includes at least one selected from the group consisting of an organic compound containing a hydroxyl group, an organic compound containing a carbonyl group, an inorganic acid and inorganic salt, hydrofluoric acid, ammonium fluoride and an organic acid.

Abstract: A metal film such as an aluminum film or an aluminum alloy film is etched with good controllability, preventing a resist from bleeding, to have a proper taper configuration and superior flatness. A water solution containing a phosphoric acid, a nitric acid, and an organic acid salt is used as an etching liquid composition used to etch the metal film on a substrate. The organic acid salt is composed of one kind selected from a group consisting of an aliphatic monocarboxylic acid, an aliphatic polycarboxylic acid, an aliphatic oxicarboxylic acid, an aromatic monocarboxylic acid, an aromatic polycarboxylic acid and an aromatic oxycarboxylic acid, and one kind selected from a group consisting of an ammonium salt, an amine salt, a quaternary ammonium salt, and an alkali metal salt. In addition, a concentration of the organic acid salt ranges from 0.1% to 20% by weight.

Abstract: An etchant composition contains (a) an alkaline compound mixture of an organic alkaline compound and inorganic alkaline compound and (b) a silicon-containing compound. The organic alkaline compound is composed of one or more ingredients from quaternary ammonium hydroxide and ethylenediamine. The inorganic alkaline compound is composed of one or more ingredients from sodium hydroxide, potassium hydroxide, ammonia and hydrazine. The silicon-containing inorganic compound is composed of one or more ingredients from metal silicon, fumed silica, colloidal silica, silica gel, silica sol, diatomaceous earth, acid clay and activated clay, and the silicon-containing organic compound is composed of one or more ingredients from quaternary ammonium salts of alkyl silicate and quaternary ammonium salts of alkyl silicic acid.