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ITS-90 Calibration of Radiometers Using Wire/Thin-film Thermocouples in the NIST RTP Tool: Effective Emissivity Modeling
Published
Author(s)
Benjamin K. Tsai, D P. DeWitt
Abstract
Models were developed to estimate the wafer effective emissivity as a function of the optical properties and geometrical configuration of the wafer and chamber in the NIST Rapid Thermal Processing (RTP) tool. These estimates were used to determine wafer temperatures from observed spectral radiance temperatures obtained with a light-pipe radiation thermometer (LPRT) calibrated on the International Temperature Scale of 1990 (ITS-90) against a blackbody. Out of the total uncertainty of 3.5 C for the LPRT temperature measurements, the uncertainty component due to the effective emissivity uncertainty contributed about 2.0 C. ( In this paper all uncertainties are reported with a coverage factor of k = 1.) The model-corrected LPRT temperature measurements were in agreement with measurements using the new NIST combination wire/thin-film thermocouples (TC) calibrated against the ITS-90 with an uncertainty of less than 0.4 C for the wafer temperature range 700 C to 900 C.
Proceedings Title
7th International Conference on Advanced Thermal Processing of Semiconductors
Tsai, B.
and DeWitt, D.
(1999),
ITS-90 Calibration of Radiometers Using Wire/Thin-film Thermocouples in the NIST RTP Tool: Effective Emissivity Modeling, 7th International Conference on Advanced Thermal Processing of Semiconductors
(Accessed October 11, 2025)