Fermi Level in Intrinsic Semiconductors

The probability of an electron being thermally excited to a conduction band is given by the Fermi fimction times the density of states at Ec 

If the density of states below the valence band g(Ey) is the same as the density of states above the conduction band g Ec), it may be seen that the Fermi level is Ep = (Ec-l-Ev)/2 

Lattice Parameters and Bandgap Energies for Selected Semiconductors 

Sources Data taken from Gersten, J.I. and Smith, F.W. The Physics and Chemistry of Materials, John Wiley Sons, New York, 2001 Kittel, C., Introduction to Sdid State Physics, 7th edn. John Wiley Sons, New York, 1966 Navon, D.H., Electronic Materials and Devices, Houghton Mifflin, Boston, MA, 1975. 

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