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Wafer Emissivity Effects on Light Pipe Radiometry in RTP Tools



Kenneth G. Kreider, David W. Allen, D H. Chen, D P. DeWitt, Christopher W. Meyer, Benjamin K. Tsai


We investigated the effect of different wafer emissivities and the effect of low emissivity films on RTP wafer temperature measurements using light pipe radiation thermometers (LPRTs). These tests were performed in the NIST RTP test bed. We used a NIST thin-film thermocouple (TFTC) calibration wafer to calibrate the LPRTs in situ. The measurements of LPRTs viewing Au and Pt thin film spot in the center of the wafer were compared to LPRT readings that viewed bar Si/SiO2. We found differences of up to 36 C at 900 C in the LPRT measurements due to the low emissivity films. A model of the wafer temperature measurement is presented to provide an insight into the effects of wafer emissivity on LPRT measurements in RTP tools.
International Conference on the Electro Chemical Society


emissivity, in situ calibration, light pipe thermometer, radiometry, rapid thermal processing, thin-film thermocouples


Kreider, K. , Allen, D. , Chen, D. , DeWitt, D. , Meyer, C. and Tsai, B. (2002), Wafer Emissivity Effects on Light Pipe Radiometry in RTP Tools, International Conference on the Electro Chemical Society (Accessed May 30, 2024)


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Created May 1, 2002, Updated February 17, 2017