Method of manufacturing semiconductor device, substrate processing method, non-transitory computer-readable recording medium and substrate processing apparatus

A method of processing a substrate, comprising:

• (a) loading the substrate with a film formed on a surface thereof into a process vessel;
• (b) generating a reactive species containing oxygen and a reactive species of helium by converting a mixed gas containing a helium gas and an oxygen-containing gas into a plasma state;
• and
• (c) oxidizing the film by supplying the reactive species containing oxygen to the substrate together with the reactive species of helium such that the reactive species of helium penetrates into the film,
• wherein, in (b), a partial pressure ratio PN/PT, which is a ratio of a partial pressure PN of the helium gas in the process vessel to a total pressure PT of the mixed gas in the process vessel, is set to a value of 0.04 or more and 0.2 or less and is selected within a range at which a first wet etching rate of the film after being oxidized by sequentially performing (b) and (c) is equal to or less than a second wet etching rate of the film oxidized by supplying, in (b), the reactive species containing oxygen to the substrate in the process vessel without supplying the reactive species of helium thereto,
• wherein the first wet etching rate and the second wet etching rate are wet etching rates with respect to an aqueous solution of hydrogen fluoride, and
• wherein a distance from a plasma generation space where the reactive species containing oxygen and the reactive species of helium are generated in (b) to the substrate is set to a distance where at least a part of the reactive species of helium reaches a surface of the film without being deactivated.

A non-transitory computer-readable recording medium storing a program that causes, by a computer, a substrate processing apparatus to perform:

• (a) loading a substrate with a film formed on a surface thereof into a process vessel;
• (b) generating a reactive species containing oxygen and a reactive species of helium by converting a mixed gas containing a helium gas and an oxygen-containing gas into a plasma state;
• and
• (c) oxidizing the film by supplying the reactive species containing oxygen to the substrate together with the reactive species of helium such that the reactive species of helium penetrates into the film,
• wherein, in (b), a partial pressure ratio PN/PT, which is a ratio of a partial pressure PN of the helium gas in the process vessel to a total pressure PT of the mixed gas in the process vessel, is set to a value of 0.04 or more and 0.2 or less, and
• wherein a distance from a plasma generation space where the reactive species containing oxygen and the reactive species of helium are generated in (b) to the substrate is set to a distance where at least a part of the reactive species of helium reaches a surface of the film without being deactivated.