The accurate modeling of the temperature response of semiconductor production wafers during rapid thermal processing

When a production semiconductor with un-relaxed ion-implanted regions or wafer is subject to external irradiation, a portion of the incident energy is absorbed within the wafer volume, rather than at the surface. The volume absorption will alter the distribution of energy within the wafer, resulting in temperature non-uniformity. In order to access the contribution of the volume absorption and emission processes the mathematical model and Fortran code was developed. The model of one-dimensional transient problem solves the energy equation in conjunction with the radiation problem using the Crank-Nicholson scheme. Input to the model includes material properties specified in a look-up table form. The spectral ellipsometry was used to determine the optical properties of the ion-implanted layers. The model showed the difference in the surface temperature of the wafer similar to the results observed experimentally.