Method of manufacturing integrated circuit device

A method of manufacturing an integrated circuit device, the method comprising:

• forming, on a substrate, a stack structure that includes a plurality of hafnium oxide films and a plurality of intermediate films that are alternately arranged in a vertical direction;
• forming an opening that passes through the stack structure in the vertical direction;
• and
• etching a portion of each of the plurality of hafnium oxide films exposed by the opening,
• wherein etching the portion of each of the plurality of hafnium oxide films comprises:
• performing a dry treatment that changes components of a surface region of each of the plurality of hafnium oxide films by isotropically exposing each of the plurality of hafnium oxide films exposed by the opening to a gas mixture, wherein the gas mixture includes a halogen element-containing gas and a catalytic gas that includes hydrogen atoms, in an atmosphere in which no plasma is applied onto the substrate, wherein the surface region extends from an exposed surface of each of the plurality of hafnium oxide films into each of the plurality of hafnium oxide films by as much as a predetermined thickness;
• performing a wet treatment with an acidic solution that removes at least a portion of the component-changed surface region from each of the plurality of hafnium oxide films;
• and
• forming an indent space that extends in a horizontal direction between the plurality of intermediate films and is connected with the opening, by repeating a sequence of the dry treatment and the wet treatment.

A method of manufacturing an integrated circuit device, the method comprising:

• alternately stacking a plurality of insulating films and a plurality of sacrificial insulating films on a substrate;
• forming a vertical hole that extends in a vertical direction through the plurality of insulating films and the plurality of sacrificial insulating films to;
• sequentially forming a hafnium oxide film, a channel layer, and an insulating plug on exposed surfaces in the vertical hole;
• forming a plurality of gate spaces by removing the plurality of sacrificial insulating films;
• etching portions of the hafnium oxide film through the plurality of gate spaces such that each of the plurality of gate spaces is expanded in a horizontal direction;
• and
• forming a plurality of gate lines that fill the plurality of gate spaces,
• wherein etching the portions of the hafnium oxide film comprises:
• performing a dry treatment that changes components of a surface region of the hafnium oxide film by isotropically exposing the hafnium oxide film to a gas mixture, wherein the gas mixture includes a halogen element-containing gas and a catalytic gas that includes hydrogen atoms in an atmosphere in which no plasma is applied onto the substrate, wherein the surface region extends from an exposed surface of the hafnium oxide film into the hafnium oxide film by as much as a predetermined thickness;
• performing a wet treatment using an acidic solution that removes at least a portion of the component-changed surface region from the hafnium oxide film;
• and
• repeating a sequence of the dry treatment and the wet treatment.