Patent Number:
6,250,914
Title:
Wafer heating device and method of controlling the same
Abstract:
The present invention provides a wafer heating device which can improve uniformity of a temperature distribution within a surface area of a wafer, with a relatively simple structure. A wafer is supported on a susceptor of annular shape. A first heater of disc shape is disposed below the wafer, and a second heater of annular shape is disposed to surround the first heater. Radiation thermometers are arranged at a ceiling portion of a reaction chamber. The first radiation thermometer measures a temperature of a central area of the wafer, the second radiation thermometer measures a temperature of a peripheral area of the wafer, and the third radiation thermometer measures a temperature of the susceptor. The first heater and the second heater are controlled by independent closed loops. When a wafer is set on the susceptor, a power of the second heater is controlled by using a value measured by the second radiation thermometer as a feedback signal. When no wafer is set on the susceptor, the power of the second heater is controlled by using a value measured by the third radiation thermometer as a feedback signal.
Inventors:
Katsumata; Hirofumi (Fuji, JP), Ito; Hideki (Numazu, JP), Takahashi; Hidenori (Numazu, JP), Ohashi; Tadashi (Kanagawa-ken, JP), Tobashi; Shuji (Sagamihara, JP), Iwata; Katsuyuki (Numazu, JP)
Assignee:
Toshiba Machine Co., Ltd
International Classification:
C30B 25/10 (20060101); C23C 16/46 (20060101); C30B 25/16 (20060101); C23C 16/52 (20060101); H01L 21/00 (20060101); F27D 007/06 ()
Expiration Date:
06/26/2018