If ${n_e}$ and ${n_h}$ are the number of electrons and holes in a semiconductor heavily doped with phosphorus,then

Through a semiconductor,an electric current is due to the drift of

$A$ crystal of intrinsic silicon at room temperature has a carrier concentration of $1.6 \times 10^{16} / m^3$. If the donor concentration level is $4.8 \times 10^{20} / m^3$, then the concentration of holes in the semiconductor is

In a sample of pure silicon,$10^{13} \text{ atoms/cm}^3$ of phosphorus is added. If all donor atoms are active,what will be the resistivity at $20 ^oC$ if the mobility of electrons is $1200 \text{ cm}^2/\text{V} \cdot \text{s}$? (in $\Omega \cdot \text{cm}$)

Write four points in distinguishing between $p$-type semiconductor and $n$-type semiconductor.

In $n$-type semiconductor,electrons are majority charge carriers,but it does not show any negative charge. The reason is: