In the energy band diagram of a material shown below, open circles and filled circles denote holes and electrons respectively. The material is a

Step-by-step solution

The energy band diagram shows a valence band (lower) and a conduction band (upper) separated by an energy gap E_g . In the valence band, there are both filled circles (electrons) and open circles (holes). The presence of holes in the valence band indicates that some electrons have been excited to the conduction band or that the material is doped such that there is a deficiency of electrons in the valence band. In the conduction band, there are filled circles (electrons). Since the number of holes in the valence ban