Substrate processing method and substrate processing apparatus

A substrate processing apparatus, comprising:

• a vacuum chamber configured to accommodate a substrate;
• a chlorine gas supply configured to supply chlorine gas to the substrate in the vacuum chamber;
• a source gas supply configured to supply a source gas to the substrate in the vacuum chamber;
• a nitriding gas supply configured to supply a nitriding gas to the substrate in the vacuum chamber;
• and
• a controller, wherein
• the chlorine gas supply includes:
• a retaining portion configured to retain the chlorine gas before being supplied to the substrate in the vacuum chamber, and
• a light source configured to emit an ultraviolet ray to irradiate the chlorine gas inside the retaining portion,
• the controller is configured to execute:
• preparation of the substrate having a recess on a surface thereof,
• supply of the chlorine gas to the substrate, thereby forming an adsorption-inhibiting layer in the recess,
• supply of the source gas to the substrate, thereby forming a molecular layer of the source gas in the recess, and
• supply of the nitriding gas to the substrate, thereby nitriding the molecular layer formed in the recess,
• the source gas is a gas that is inhibited by the adsorption-inhibiting layer from the formation of the molecular layer in the recess, and
• the formation of the adsorption-inhibiting layer includes:
• retaining, in the retaining portion, the chlorine gas before being supplied to the substrate, and
• generating chlorine radicals from the chlorine gas by irradiating, with the ultraviolet ray, the chlorine gas inside the retaining portion.