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Doped semiconductors

  1. Jun 4, 2010 #1
    If we have two semiconducting materials say silicon and germanium and in this specific case silicon has a very large donor area energy say 25Mev and a very small energy gap, say 1.1Mev and germanium has a smaller energy gap then silicon, 0.6Mev and a donor energy of 2Mev.

    I amtrying to figure out the logic of this.Does having a larger donor area energy mean that it is harder for the electrons to move into the conductive band?

    And how would i figure out which is more likely to intrinsic and extrinsic carriers in the conduction band at room temperature?

    and how would this change with increasing temperature?
  2. jcsd
  3. Jun 4, 2010 #2


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    Er.... MEGA electron volts?!!

  4. Jun 7, 2010 #3
    The band gaps shown in your post are in eV (and not MeV - megaelectron volts).
    The energies of the donor levels are much lower, of the order of tens of millielectronvolts (meV). Maybe a confusion regrading the notations?
    Kittel gives the energy of the impurity levels in meV, for example.
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