Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Difference between hole and +ve ion?

  1. Mar 5, 2010 #1
    Can anybody tell me what actually is difference between between electron hole and positive ion.
     
  2. jcsd
  3. Mar 6, 2010 #2

    marcusl

    User Avatar
    Science Advisor
    Gold Member

    If an atom in an intrinsic semiconductor (SC) is excited thermally so an electron jumps from the valence band to the conduction band, then the electron is free and the atom becomes a positive ion. This is called a hole. If an electric field is applied across the material, free electrons will drift to carry a current. If a free electron created elsewhere in the lattice collides with the hole they recombine into a neutral atom--but there is a hole left where that electron came from. It looks like holes drift too, opposite to the electrons. Because they are charged positively, they also contribute to carrying current. Notice that the ion itself doesn't move, because it is bound in the crystal lattice. It's the hole that moves. That's the difference.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook