The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 26, 2001
Filed:
Apr. 21, 2000
Hirofumi Katsumata, Fuji, JP;
Hideki Ito, Numazu, JP;
Hidenori Takahashi, Numazu, JP;
Tadashi Ohashi, Kanagawa-ken, JP;
Shuji Tobashi, Sagamihara, JP;
Katsuyuki Iwata, Numazu, JP;
Other;
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.