Which one of the following statements refers to semiconductors? One correct answer.
▢ A. The valence band is partially filled with electrons.
▢ B. The valence band is fully filled with electrons and the conduction band is empty but
overlaps with the valence band.
▢ C. The valence band is fully filled with electrons and the conduction band is partially filled with
electrons, but it does not overlap with the valence band.
▢ D. The valence band is fully filled with electrons and the conduction band is separated from
the valance band by a small energy gap, for which absorption of visible light can promote
electrons in the conduction band.
▢ E. The valence band is fully filled with electrons and the conduction band is separated from
the valance band by a large energy gap, for which absorption of visible light cannot promote
electrons in the conduction band