Electronic structure of ultraheavily doped silicon

The electronic structure of ultraheavily doped silicon has been calculated for impurity concentrations ranging from 0.5×${10}^{21}$ to ${10}^{22}$ ${\mathrm{cm}}^{-3\mathrm{}}$. The system has been modeled by a realistic tight-binding Hamiltonian with diagonal disorder and solved within the coherent potential approximation. The results have been compared with reported shifts of the absorption edge.