To provide a device for controlling the temperature of a
wafer by adjusting the pressure or flow rate of a gas, in which the temperature of a first region where
temperature measurement is possible or the temperature in the vicinity of the first region is measured, and the temperature of a second region where
temperature measurement is difficult is controlled to a target temperature.SOLUTION: A
wafer temperature control device 100 in which a
wafer W is placed on a temperature-adjusted plate 2 and gas is supplied between the plate 2 and the wafer W to control the temperature of the wafer W, includes a gas
regulator 43 that adjusts the pressure or flow rate of the gas, a temperature sensor 5 that measures the temperature of a measurement target region W2 or its vicinity on the wafer W, an observer 10 for estimating the temperature of a non-measurement target region W1 different from the measurement target region W2 of the wafer W based on the measured temperature of the temperature sensor 5 and a gas operation amount input to the gas
regulator 43 or the pressure or flow rate adjusted by the gas
regulator 43, and a gas
control unit 11 that controls the gas operation amount input to the gas regulator 43 by
model predictive control based on the estimated temperature of the non-measurement target region W1 estimated by the observer 10 and the target temperature of the wafer W.SELECTED DRAWING: Figure 3