Film forming apparatus, cleaning method for film forming apparatus and recording medium

A film forming apparatus configured to perform a film forming processing by supplying a plasmarized processing gas onto a substrate, the film forming apparatus comprising:

• a mounting unit provided within a processing vessel in which a vacuum atmosphere is formed and configured to mount the substrate thereon;
• a processing gas discharge unit having a facing surface portion which faces the mounting unit and gas discharge holes opened to the facing surface portion for discharging a processing gas;
• a cleaning gas supply unit configured to supply a cleaning gas for removing a film formed within the processing vessel;
• a plasma generating mechanism commonly used for plasmarizing the processing gas and the cleaning gas supplied into the processing vessel;
• an exhaust device configured to evacuate an exhaust line connected to the processing gas discharge unit while the plasmarization of the cleaning gas is being performed by the plasma generating mechanism;
• a tank provided at the exhaust line via a first valve, and connected to a processing gas source via a second valve, and connected to the exhaust device via a third valve;
• the first valve which is provided at the exhaust line between the tank and the processing gas discharge unit;
• and
• a control unit configured to
• control the first valve to open the exhaust line, the second valve to open the processing gas source, and the third valve to close the exhaust device in order to supply the processing gas into a processing space,
• control the first valve to close the exhaust line, the second valve to close the processing gas source, and the third valve to open the exhaust device in order to reduce an internal pressure of the tank by using the exhaust device, and
• control the first valve to open the exhaust line, the second valve to close the processing gas source, and the third valve to open the exhaust device to attract the plasmarized cleaning gas into the tank from the processing space through the processing gas discharge unit by using the exhaust device,
• wherein the exhaust line serves to supply the processing gas and drain the cleaning gas in different time periods.