| 摘要 |
PROBLEM TO BE SOLVED: To unify the flatness of a wafer after the grinding by providing a temperature adjusting mechanism provided on at least a lower surface plate of the upper and lower surface plates for reducing the temperature difference of a surface to be grinded. SOLUTION: The grooves 66 formed on the lower bases 65 of a lower surface plate 2 are independently connected to the temperature adjustment circuits and each temperature adjustment circuit comprises a temperature sensor as a detecting member, a hot water supply device, and a temperature adjusting unit for arbitrarily setting a temperature of the hot water to be supplied from the hot water supply device when it receives a signal from the temperature sensor. This temperature adjusting unit executes the proportional control for proportionally changing an output signal to an input signal. That is, the water temperature can be independently adjusted by each temperature adjustment circuit, and the flatness of the surface of the lower surface plate 2 can be changed by supplying the hot water of different temperature to each base 65. Whereby the flatness state of the wafer can be easily changed. |
