Bichannel radiation detection method
US5114242A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1990 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Dec 7, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/60
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The system and method for pyrometrically determining the temperature of a semiconductor wafer within a processing chamber accurately determines the actual emissivity of the semiconductor wafer at a reference temperature using multiple pyrometers operating at different wavelengths. The pyrometers are calibrated for radiation received from the processing chamber and their responses are then corrected to provide the proper temperature indication for a master wafer at a known reference temperature to yield emissivity of the master wafer. Other similar wafers exhibiting extreme values of emissivity are sensed at the reference temperature to provide pyrometer responses that are corrected in accordance with the master emissivity, and such corrected responses are used to establish a correlation between emissivities and the corrected pyrometer responses. The corrected pyrometer responses on other wafers operating near the reference temperature can then be used with the emissivities to determine the true temperature of each such other wafer. The processing temperature of the wafer is then determined and controlled in accordance with the actual emissivity of the wafer for more precise thermal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.