Charge carrier density

Charge carrier density denotes the number of charge carriers per volume. It is measured in m⁻³. As any density it can depend on position. It should not be confused with the charge density, which is the number of charges per volume at a given energy.

The carrier density is obtained by integrating the charge density over the energy that the charges are allowed to have.

Charge carrier density is a particle density, so integrating it over a volume ${\displaystyle V}$ gives the number of charge carriers ${\displaystyle N}$ in that volume

${\displaystyle N=\int _{V}n(\mathbf {r} )\,\mathrm {d} V}$.

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