The Energy Band Model

Model Description
Definitions
The Conduction Band
The Valence Band
The Band Gap Energy
Material Classification
Doping
Related Topics

The Band Gap Energy:

The band gap energy is the energy needed to break a bond in the crystal. When a bond is broken, the electron has absorbed enough energy to leave the valence band and "jump" to the conduction band. The width of the band gap determines the type of material (conductor, semiconductor, insulator) you are working with. This is shown pictorially using a band diagram.
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