A hybrid-type surface temperature sensor and its application to the development of emissivity compensated radiation thermometry

The authors devised a hybrid-type surface temperature sensor that combines the advantage of contact and noncontact method and provide a way to overcome the weak points of both methods. This sensor is composed of two main components: a thin metallic film that makes contact with the object, and an optical sensor that is used to detect the radiance of the rear surface of the film. The temperature measurement using this sensor is possible with an uncertainty of 1 K and the response time within 1 s in the temperature range 600 K to 1000 K. The authors confirmed that this hybrid-type sensor was valid for the in situ temperature monitoring of silicon wafers. By use of this sensor as a calibration device of the surface temperature of a silicon wafer, the authors tried to develop the emissivity compensated radiation thermometry of silicon wafers. An excellent relation between the ratio of polarized radiances and polarized emissivities was found, which is to lead to a promising method for a simultaneous measurement of temperature and emissivity of silicon wafers irrespective of emissivity change. In this paper, experimental results are detailed.