Substrate processing apparatus and manufacturing method of semiconductor device

A substrate processing apparatus comprising:

• a substrate holder that holds a plurality of substrates arrayed at predetermined intervals;
• a tubular reactor that has a cylindrical shape that extends in a vertical direction, the tubular reactor including a ceiling at an upper end and an opening portion that is opened at a lower end, and housing the substrate holder in a manner such that the substrate holder can be carried in and out through the opening portion, and;
• a cylindrical inlet flange connected to the lower end of the tubular reactor and including a plurality of gas introduction ports on an outer peripheral surface;
• a lid that closes a lower end opening of the inlet flange in a manner such that the substrate holder can be carried in and out;
• temperature sensors thermally coupled to the inlet flange or heater elements and configured to detect temperatures;
• the heater elements disposed along the inlet flange while avoiding the gas introduction ports, a number of the heater elements is greater than N that is a number of the temperature sensors;
• and
• a temperature controller configured to divide the heater elements into groups of N and control power supply to the respective groups of heater elements independently based on detection temperatures detected by the corresponding temperature sensors.