Bichannel radiation detection method
Patent 5114242 Issued on May 19, 1992. Estimated Expiration Date: 
December 7, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 7, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorsApplicationNo. 624206 filed on 12/07/1990US Classes:374/128, Having significant signal handling circuitry (e.g., linearizing, emissivity compensation)374/126, Having emissivity compensating or specified radiating surface374/129Comparison with radiation reference standardExaminersPrimary: Cuchlinski, William A. Jr.Assistant: Gutierrez, Diego Attorney, Agent or FirmForeign Patent References
International ClassesG01J 005/62G01J 005/60 G01J 005/54 G01J 005/10 AbstractThe 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 processing.Other References
Field of SearchTHERMAL CALIBRATION SYSTEMEMISSIVITY DETERMINATION Having emissivity compensating or specified radiating surface Having significant frequency limitation or relationship (e.g., peak, ratio) Having significant signal handling circuitry (e.g., linearizing, emissivity compensation) Comparison with radiation reference standard Infrared responsive Plural color responsive | |
