Dpletion region

pic taken from hyperphysics
The P and N type when put together would create depletion region .A region where the electrons have fallen into the holes. This region would be lack of any electrons and holes!When a hole in the depletion region is filled by an electron ,the atom becomes a negative ion, Where the electron left behind in the depletion region is a positive ion An electric field is set up within the depletion region.
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