Temperature dependence of p-polarized transmittance of a semitransparent silicon wafer and its application to non-contact temperature measurement

Radiation thermometry is a preferable method for a manufacturing process of silicon wafers because this is a non-contact, contaminant free method. This method is, however, difficult to apply for silicon wafers under 600°C, because the wafer becomes semitransparent. We have studied an alternative method based upon the transmittance variation that is available for a relatively low temperature under 600°C. In this study, we obtained experimental results that there was a stable relation between the p-polarized transmittance and temperature irrespective of wide variations of oxide film thickness grown on silicon wafers. The advantage and disadvantage of this method was compared with an absorption edge wavelength shift method that was carried out previously.