Heat treatment apparatus

A heat treatment apparatus for performing a heat treatment on a plurality of target objects held by a holding unit by allowing an inert gas to flow upwardly in a vertical processing container with a heating unit provided in the vicinity of the processing container, the apparatus comprising:

• a main temperature control unit configured to control the heating unit;
• an inert gas passage through which the inert gas flows into the processing container;
• an inert gas heating unit installed in the inert gas passage and configured to heat the inert gas;
• a first temperature measuring unit located in the inert gas heating unit;
• a heat insulation heater installed along the inert gas passage between the inert gas heating unit and the processing container;
• a second temperature measuring unit installed in the heat insulation heater;
• a lower portion heating unit installed along the circumferential direction of the processing container and configured to heat the inert gas introduced into the processing container;
• a third temperature measuring unit installed in the lower portion heating unit;
• a lid heating unit installed in a lid for air-tightly sealing a bottom opening of the processing container;
• a fourth temperature measuring unit installed in the lid heating unit;
• and
• a temperature controller configured to control the inert gas heating unit, the heat insulation heater, the lower portion heating unit and the lid heating unit based on temperatures measured by the first to the fourth temperature measuring units,
• wherein when predetermined values of processing temperatures vary during the heat treatment, the temperature controller controls the inert gas heating unit to reflect changes of the predetermined values such that the target objects accommodated in the processing container can have a uniform heat history, and controls at least one of the heat insulation heater, the lower portion heating unit and the lid heating unit to reflect changes of the predetermined values based on the temperatures measured by the second to the fourth temperature measuring units.