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CH1012
CONDUCTIVITY
Metal – the valence and
conduction bands overlap,
there is no band gap ® high conductivity.
Conductivity decreases with temperature T
there is no band gap ® high conductivity.
Conductivity decreases with temperature T
Semiconductor - there is a small band gap and so thermally
excited electrons will cross the gap
® low conductivity. Conductivity increases with T
® low conductivity. Conductivity increases with T
Insulator - a large band gap ® no conductivity.
The energy
gap between the valence band and
the conduction band is usually called the band gap
the conduction band is usually called the band gap
