Gas supply apparatus and film forming apparatus

A gas supply apparatus equipped with a processing container for performing a film forming process for an object to be processed, comprising:

• a raw material gas supply system configured to supply a raw material gas carried with a carrier gas into the processing container;
• a raw material storage tank having a gas inlet for introducing the carrier gas and a gas outlet connected to a gas passage through which the raw material gas carried with the carrier gas flows, and configured to store a liquid raw material;
• a main heating unit configured to heat a bottom and sides of the raw material storage tank to generate the raw material gas;
• a ceiling heating unit configured to heat a ceiling portion of the raw material storage tank;
• a main temperature measurement unit configured to measure a temperature of a region in which the main heating unit is disposed;
• a ceiling temperature measurement unit configured to measure a temperature of a region in which the ceiling heating unit is disposed;
• a liquid phase temperature measurement unit configured to measure a temperature of the liquid raw material stored in the raw material storage tank;
• a vapor phase temperature measurement unit configured to measure a temperature of a vapor phase portion in the upper part of the raw material storage tank;
• a level measurement unit configured to measure a liquid level of the liquid raw material;
• and
• a temperature control unit configured to control the main heating unit and the ceiling heating unit,
• wherein the temperature control unit is operated to perform a first process of determining whether to proceed to a second process based on a measurement of the main temperature measurement unit, a measurement of the liquid phase measurement unit, and a predetermined set temperature, and, if it is determined not to proceed to the second process, controlling the main heating unit and the ceiling heating unit based on the set temperature, and the second process of obtaining a control temperature based on measurements of the main temperature measurement unit, the liquid phase temperature measurement unit, the vapor phase temperature measurement unit and the level measurement unit, and controlling the main heating unit and the ceiling heating unit based on the control temperature.