All
energy levels in the valence band are filled while energy levels in the
conduction band may be fully empty or partially filled The electrons in
the conduction band are free to move in a solid and are responsible for
the conductivity The extent of conductivity depends upon the energy
gap (Eg) between the top of valence band (EV ) and the bottom of the
conduction band EC The electrons from valence band can be excited by
Rationalised 2023-24
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Semiconductor Electronics:
Materials, Devices and
Simple Circuits
heat, light or electrical energy to the conduction band and thus, produce
a change in the current flowing in a semiconductor