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Why do charges accumulate at grain boundaries?

  1. Oct 15, 2013 #1
    The concept of "space charge" around grain boundaries keeps coming up in my reading. I understand that charges tend to build up at grain boundaries, but I'm not sure why. Can someone explain what "draws" charges to boundaries?
  2. jcsd
  3. Oct 15, 2013 #2


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    The internal potential for the neighboring grains differ due to strain and imperfections. This generates an effective field between the grains.
  4. Oct 16, 2013 #3


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    I think the example best understood is that of a pn junction in semiconductors.
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