Patent ID: 8257789

Claim:
A film formation method, in a vertical batch film formation apparatus, for forming a reaction product film on a plurality of target substrates by a reaction between substances derived from a source gas and a reactive gas within a process field inside a process container configured to accommodate the target substrates at intervals in a vertical direction and to be supplied with the source gas and the reactive gas, the method repeating a cycle a plurality of times while continuously rotating the target substrates at a rotational speed to laminate thin films formed by respective times, the cycle comprising in order: an adsorption step of performing supply of the source gas to the process field, thereby adsorbing source substances derived form the source gas onto a surface of the target substrates; a first purge step of exhausting gas from the process field without performing supply of the source gas and the reactive gas to the process field; a reaction step of performing supply of the reactive gas to the process field, thereby causing reactive substances derived from the reactive gas to react with the source substances adsorbed on the surface of the target substrates; and a second purge step of exhausting gas from the process field without performing supply of the source gas and the reactive gas to the process field, wherein the adsorption step makes a plurality of times a supply sub-step of performing supply of the source gas to the process field with an intermediate sub-step of stopping supply of the source gas to the process field interposed therebetween, while maintaining a shut-off state of supply of the reactive gas to the process field, and wherein the reaction step continuously performs supply of the reactive gas to the process field, while maintaining a shut-off state of supply of the source gas to the process field.