Patent ID: 11967512
Assignee: KOKUSAI ELECTRIC CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A substrate processing apparatus comprising:
a reaction tube provided with a furnace opening at one end thereof through which a first boat accommodating a plurality of substrates is to be inserted, wherein a process chamber in which the plurality of the substrates are processed is provided in the reaction tube;
a plurality of heaters provided on an outer periphery of the reaction tube and respectively in a plurality of zones arranged along a tube axis direction from a furnace opening side to another end of the reaction tube, wherein each of the plurality of the zones corresponds to a single heater among the plurality of the heaters and comprises a unit to be individually controlled;
a plurality of temperature sensors configured to measure temperatures of the zones or temperatures of the heaters respectively corresponding to the plurality of the zones;
a temperature controller configured to control electric power supplied to each of the heaters based on temperature data obtained by the plurality of the temperature sensors to adjust each of the temperatures of the zones; and
a furnace opening assembly comprising a lid configured to close the furnace opening; and a rotator provided at the lid and configured to rotate the first boat,
wherein the plurality of zones comprise upper zones and lower zones located closer to the furnace opening than the upper zones are located, the upper zones being located over a height range equivalent to that of the substrates accommodated in the first boat whereas the lower zones are located within a height range excluding that of the substrates accommodated in the first boat, and the plurality of the heaters comprising upper heaters of the upper zones and lower heaters of the lower zones,
wherein the temperature controller is further configured to, when the plurality of the substrates are subject to a heat treatment process by the plurality of the heaters, control the electric power supplied to the plurality of the heaters such that temperatures of the upper heaters reach a first temperature of around 1,250° C. or higher, and that a temperature gradient is formed in the lower zones such that a temperature decreases toward the furnace opening, and
wherein the lower zones comprise a first zone and a second zone located closer to the furnace opening than the first zone is located such that a bottom of the second zone has a same height as a bottom of the plurality of heaters, the first zone and the second zone of the lower zones respectively have a first length and a second length along the tube axis direction, and the first length is shorter than or equal to half of the second length.