Measurement of Thermal Radiative Properties of Silicon Wafers with Oxide Film and Nitride Film at 950°C

Abstract

The normal spectral emissivity, reflectance and transmittance of silicon wafers were measured at a temperature of 950°C and wavelengths of 0.7 to 9μm. The samples were seven silicon wafers with oxide films of 2.2 to 628nm film thickness and nitride films of 48 to 193nm film thickness with small dopant density. It was found that the emissivities of specular surfaces of silicon wafers with very thin oxide films at wavelengths of 0.7 to 8μm were 0.6 to 0.7, the reflectances were 0.1 to 0.3 and the transmittances were 0 to 0.2. The emissivity of silicon wafers with oxide films of more than 75nm film thickness and nitride films of more than 48nm film thickness changed from 0.6 to 1.0 according to film thickness and wavelength. The emissivities and reflectances of silicon wafers were calculated using the free carrier absorption theory considering the interference phenomenon. Calculated results agreed with experimental results.