Boltzmann factor for a gap. Very small numbers,
but compare with Avogadros number. For large gaps, not
even the Avogadro can compensate. Nearly pure zero
in the conduction band - insulator.
Electrons and holes. Semiconductoe conductivity
i n c r e a s e s
with temperature. Demonstrations of energy gap:
electrical conductivity, photoconductivity, or
simply absorption of photons. Phonon assisted
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