Ok, so in an intrinsic semiconductor we know that the intrinsic concentration ([itex] n_i [/itex]) is roughly [itex] 10^10 cm^{-3} [/itex] at room temperature, and that [itex] n=p=n_i [/itex] under equilibrium conditions.(adsbygoogle = window.adsbygoogle || []).push({});

Now why is it that at zero temperature, (i.e. [itex] 0K [/itex]) does [itex] n_i [/itex] have any value? I know that that [itex] n_i [/itex] does have a temperature dependence, but why any value at 0K?

Also, another question. If an intrinsic semiconductor is in equilibrium it has no current correct (lack of diffusion)? So does an intrinsic semiconductor in equilibrium have any electrons in the conduction band?

What's confusing me are the "standard" diagrams (of extrinsic) semiconductors that show the energy levels of the conduction band, valence band, donor and acceptor energy levels. It shows that at 0K, there are no electrons in the conduction band (so wouldn't n=0 !!! ???; so how can np=ni^2), next the energy is increased and some electrons jump energy levels from the donor to the conduction band, etc...

I would appreciate any input here, I have a test on Tuesday... and I do not want to just be algebra crunching out the answers. I feel I'm missing something fundamental here. Thanks in advance.

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# Basic Semiconductors (intrinsic concentration)

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