Patent ID: 8536491

Claim:
A semiconductor furnace comprising: a vertical thermal reaction chamber for processing a batch of wafers, said vertical thermal reaction chamber having a sidewall defining a height and an internal cavity for removably holding the batch of wafers; a wafer boat positionable in the vertical thermal reaction chamber and being configured and adapted to hold a plurality of wafers in vertically-stacked relationship; and a heating system comprising: a plurality of rotatable sidewall heaters spaced along the height of the reaction chamber, whereby heating by the rotatable sidewall heaters results in a temperature profile within the vertical thermal reaction chamber, the sidewall heaters being rotatable with respect to the vertical thermal reaction chamber about a rotational axis, wherein each sidewall heater is provided on an annular rotating heater base having a gear ring disposed thereon; a motor-driven gear drive provided for each of the plurality of sidewall heaters, said motor-driven gear drive engaging the gear ring for rotating the annular rotating heater base and thereby controllably rotating the sidewall heaters for controlling the temperature profile within the vertical thermal reaction chamber while the batch of wafers are being processed in the vertical thermal reaction chamber; and a motor controller for controlling the rotation of the sidewall heaters.