TWI573213B

In a conditioning method conditions interiors of a plurality of process chambers of a substrate processing apparatus, conditioning of the interior of the first process chamber is performed if a first integrated value set in connection with the process of the substrate reaches a set value N1. The second process chamber is set in a standby state when the conditioning of the first process chamber starts and the series of processes is stopped. By determining whether a second integrated value set in connection with process of the substrate in the second process chamber is equal to or greater than a set value N2, count of a third integrated value in the second process chamber is started if the second integrated value is equal to or greater than the set value N2. A conditioning of the second process chamber is performed if the third integrated value exceeds a set value N3.