Composition for etching and method for manufacturing semiconductor device using same
View Patent ↗A composition for etching and a method of manufacturing a semiconductor device, the method including an etching process of using the composition for etching, are provided. The composition for etching includes a first inorganic acid; any one first additive selected from the group consisting of phosphorous acid, an organic phosphite, a hypophosphite, and mixtures thereof; and a solvent. The composition for etching is a high-selectivity composition for etching that can selectively remove a nitride film while minimizing the etch rate for an oxide film and does not have a problem such as particle generation, which adversely affects device characteristics.
1 . A method for forming a cell gate structure, the method comprising:
forming a cell gate structure on a substrate by alternatively stacking a plurality of interlayer insulating layers and a plurality of gate electrode layers;
forming a plurality of holes through the cell gate structure; and
selectively etching a plurality of nitride layers in the cell gate structure by a composition,
wherein the composition for etching comprises:
a first inorganic acid,
a first additive, being a hypophosphite,
a second additive comprising a compound selected from Chemical Formulas 350, and
a solvent,
wherein:
(In Chemical Formula 350, each R 2 to R 5 is each independently selected from a group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aminoalkyl group having 1 to 10 carbon atoms, and an aminoalkoxy group having 1 to 10 carbon atoms, and an aryl group having 6 to 30 carbon atoms, 2 or 3 of R 2 to R 5 are hydroxy groups, and at least one of R 2 to R 5 is an alkoxy group having 1 to 10 carbon atoms, an aminoalkyl group having 1 to 10 carbon atoms or an aminoalkoxy group having 1 to 10 carbon atoms, n is an integer from 1 to 4),
wherein the composition for etching comprises the first additive at a proportion of 0.01% to 15% by weight, the first inorganic acid at a proportion of 70% to 99% by weight, the second additive at a proportion of 0.01% to 20% by weight, and the solvent as the balance.