3.5 The Influence of Strain on the Bulk Band Structure

The band structure expresses the allowed energy states in the crystal momentum space for electrons and holes. Many important electronic and optical properties are destined by the band structure.

The energy surfaces of the six conduction band valleys in unstrained silicon have a prolate ellipsodial shape. Their semi-axes represent the longitudinal $m_\mathrm{l}$ and the transversal electron mass $m_\mathrm{t}$. There are three valley pairs with coinciding minima along the three equivalent directions $\left<100\right>$.