Wafer heating device and method of controlling the same
US6250914A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 21, 2000 |
| Grant date | Jun 26, 2001 |
| Priority date | — |
| Expiry date | Apr 21, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67109
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.