Zone heating system with feedback control
US6031211A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 11, 1997 |
| Grant date | Feb 29, 2000 |
| Priority date | — |
| Expiry date | Jul 11, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/46
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A structure and method are disclosed which allow for a tighter control of the temperature across a wafer substrate. In accordance with the present invention, a wafer to be processed is heated to a constant and uniform temperature by an RF induction coil including a plurality of heating zones each of which being shunted by an associated capacitor tuned to a specific frequency. By adjusting the time during which current of a particular frequency is provided to the induction coil, current flow within, and thus the heat generated in, each of the zones may be independently controlled. Since the heat generated in the susceptor quickly changes in response to changes in current flow therein, both deviations of the wafer temperature from the processing temperature and temperature gradients across the surface of the wafer may be quickly corrected. This superior thermal response results in the present invention maintaining a wafer at a uniform temperature during heating and cooling with increased accuracy and precision.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.