Angular dependence of nonparabolicity factor of silicon band structure

This paper describes the angular dependence of the nonparabolicity factor of the silicon band structure and the influence of the angular dependence on the density of states. In order to investigate the angular dependence of the nonparabolicity factor of the band structure, we calculate the silicon band structure using the first principle calculation. In order to investigate the influence of the angular dependence on the density of states, we consider an average model to derive the average nonparabolicity factor from the information of the band structure in different directions. It is found that using the nonparabolicity factor and the effective mass in the seven directions, the average nonparabolicity factor is obtained 0.55 eV
^-1
which is close to 0.5 eV
^-1
.