Rapid-response hybrid-type surface-temperature sensor

A hybrid-type surface-temperature sensor that combines the advantages of contact and non-contact sensing methods has been developed and that offers a way to overcome the weak points of both methods. The hybrid-type surface-temperature sensor is composed of two main components: a metal film that makes contact with the object and an optical sensor that is used to detect the radiance of the rear surface of the metal film. Temperature measurement using this thermometer is possible with an uncertainty of 0.5 K after compensating for systematic errors in the temperature range from 900 to 1,000 K. The response time of our previous hybrid-type sensor is, however, as long as several tens of seconds because the measurement must be carried out under thermally steady-state conditions. In order to overcome this problem, a newly devised rapid-response hybrid-type surface-temperature sensor was developed and that can measure the temperature of an object within 1 s by utilizing its transient heat transfer response. Currently, the temperature of a silicon wafer can be measured with an uncertainty of 1.0 K in the temperature range from 900 to 1,000 K. This sensor is expected to provide a useful means to calibrate in situ temperature measurements in various processes, especially in the semiconductor industry. This article introduces the basic concept and presents experimental results and discussions. © 2008 Springer Science+Business Media, LLC.