Valence Band

For other uses, see Valence.In solids, the valence band is the highest range of electron energies where electrons are normally present at absolute zero. In semiconductors and insulators, there is a bandgap above the valence band, followed by a conduction band above that. In metals, the conduction band has no energy gap separating it from the valence band. (The rest of this article refers to the valence band in semiconductors and insulators.)
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a band of allowed energy states that exists in solids and is completely filled with electrons at zero degrees kelvin. The valence band is separted from the conduction band by an energy gap in insulators and most semiconductors and overalps the conduction band in metals.