Method of manufacturing semiconductor device, substrate processing apparatus, and recording medium

A method of improving a film thickness uniformity of a film formed on a substrate, comprising:

• forming an initial oxide layer on a surface of the substrate by performing a set m times (where m is an integer equal to or greater than 1), the set including non-simultaneously performing:
• (a) oxidizing the surface of the substrate under a condition that an oxidation amount of the substrate increases from an upstream side to a downstream side of a gas flow by supplying an oxygen-containing gas and a hydrogen-containing gas to the substrate;
• (b) oxidizing the surface of the substrate under a condition that the oxidation amount of the substrate decreases from the upstream side to the downstream side of the gas flow by supplying the oxygen-containing gas and the hydrogen-containing gas to the substrate;
• forming the film on the initial oxide layer by supplying a precursor gas to the substrate;
• wherein (a) is performed under a condition that a thickness of a first initial oxide layer formed on the surface of the substrate increases from the upstream side to the downstream side of the gas flow, and (b) is performed under a condition that the thickness of a second initial oxide layer formed on the surface of the substrate decreases from the upstream side to the downstream side of the gas flow;
• wherein in the act of forming the film on the initial oxide layer, an oxide film is formed as the film on the initial oxide layer by performing a cycle n times (where n is an integer equal to or greater than 1), the cycle including non-simultaneously performing:
• supplying the precursor gas to the substrate;
• and
• supplying the oxygen-containing gas and the hydrogen-containing gas to the substrate.