Thermophysical properties measurement of molten silicon by high-temperature electrostatic levitator: density, volume expansion, specific heat capacity, emissivity, surface tension and viscosity

Thermophysical properties of molten silicon measured by the high-temperatur e electrostatic levitator at JPL are presented. The properties include the density, the volume expansion, the constant pressure specific heat capacity , the hemispherical total emissivity, the surface tension and the viscosity . Over the temperature range investigated (1350-1850 K), the measured liqui d density showed a quadratic nature expressed by rho(T) = 2.58 - 1.59 x 10( -4) (T - T-m) - 1.15 x 10(-7) (T - T-m)(2) g/cm(3) with T-m = 1687 K. The v olume expansion with respect to the melting point could be expressed by V(T )/V-m = 1 + 6.18 x 10(-5) (T - T-m) + 4.72 x 10(-8) (T - T-m)(2). The hemis pherical total emissivity of molten silicon at the melting temperature was 0.18, and the constant pressure specific heat was determined over a 500 K a round the melting point. The measured surface tension and the viscosity cou ld be expressed respectively by sigma(T) = 765 - 0.016(T - T-m) mN/m, and e ta(T) = 0.75 - 1.22 x 10(-3) (T - T-m) mPa s. (C) 2000 Published by Elsevie r Science B.V. All rights reserved.