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This confuses me: In the wikipedia article it talks about how the majority charge carrier is electrons for an N-type semiconductor

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How come the electrons in the conduction band don't just jump into the holes present in the valence band?

An intrinsic semi-conductor is doped with an atom that has an extra electron. For example Silicon is doped with Boron. Here Boron has 5 electrons in it's valence band vs Silicon has 4 (I don't know the numbers for sure, just an example), so the extra electron has nowhere to go (maybe my way of thinking is wrong?)

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In addition to doping, electron hole pairs are cfeated thermally according to the Fermi Dirac distribution. These are called intrinsic carriers, while the ones due to impurities are extrinsic.

Furthermore, in order to recombine, electrons and holes need spatial overlap, so they must meet at tbe same position (or nearby). But even for high doping levels (above 1e18), one impurity and therefore one electron or hole is diluted in 10e4 crystal atoms. Recombination thus does not happen immediately, but statistically after a characteristic time. Keep in mind, intrinsic carriers are still generated thermally, so the carrier distributios are in an equilibrium.

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