Patent ID: 8221835

Claim:
A method of manufacturing a semiconductor device, comprising: charging a product substrate to a support; loading the support having been charged with the product substrate into a reaction furnace, processing the product substrate in the reaction furnace by supplying a reaction gas into the reaction furnace through a gas supply line, and evacuating the reaction gas through an exhaust line by driving a pump connected to the exhaust line; performing a first purge in the reaction furnace, under a state that the processed product substrate has been accommodated in the reaction furnace, with an exhaust valve connected to the exhaust line being opened, by repeating a supply and a stop of the supply of an inert gas into the reaction furnace two or more times while maintaining the driving of the pump, to generate a pressure fluctuation in the reaction furnace; unloading the support, which has supported the processed product substrate, from the reaction furnace; discharging the processed product substrate from the support, after the support has been unloaded from the reaction furnace; loading the support into the reaction furnace without charging another product substrate to the support, after the processed product substrate has been discharged from the support; and performing a second purge in the reaction furnace, under a state that the support has been accommodated in the reaction furnace, by repeating a supply of an inert gas into the reaction furnace under a state that the exhaust valve is closed and a stop of the supply of the inert gas into the reaction furnace under a state that the exhaust valve is opened two or more times, while maintaining the driving of the pump, to generate a pressure fluctuation in the reaction furnace, wherein a rate of the pressure fluctuation in the reaction furnace in the second purge is larger than a rate of the pressure fluctuation in the reaction furnace in the first purge, and a cycle of the supply and the stop of the supply of the inert gas into the reaction furnace in the second purge is shorter than a cycle of the supply and the stop of the supply of the inert gas into the reaction furnace in the first purge.