Seebeck Coefficient of Heavily P-Doped Si Calculated from an Alteration in Electronic Density of States

Abstract

We have performed a theoretical calculation of the Seebeck coefficient in heavily P-doped Si, taking into account the influence of impurity-band formation, ionization-energy shift, and conduction-band tailing. It was found that the calculated Seebeck coefficient decreased with increasing impurity concentration, with a peak around 1 × 1019 cm−3. This result is qualitatively in good agreement with experimental results, indicating that the Seebeck coefficient of the heavily doped Si is strongly influenced by the electronic density of states in the impurity band. Therefore, to enhance the Seebeck coefficient by introducing nanostructures, the Fermi energy has to be controlled without the influence of the impurity band.