$A$ pure semiconductor has equal electron and hole concentration of $10^{16} \ m^{-3}$. Doping by gallium increases $n_{h}$ to $5 \times 10^{22} \ m^{-3}$. Then,the value of $n_{e}$ in the doped semiconductor is

The addition of antimony atoms to a sample of intrinsic germanium transforms it into a material which is:

Mobility of electrons in a semiconductor is defined as the ratio of their drift velocity to the applied electric field. If,for an $n$-type semiconductor,the density of electrons is $10^{19} \ m^{-3}$ and their mobility is $1.6 \ m^2/(V \cdot s)$,then the resistivity of the semiconductor (since it is an $n$-type semiconductor,the contribution of holes is ignored) is close to ................ $\Omega \cdot m$.

In a semiconductor,the concentrations of electrons and holes are $8 \times 10^{18} \, m^{-3}$ and $5 \times 10^{18} \, m^{-3}$ respectively. If the mobilities of electrons and holes are $2.3 \, m^2/V \cdot s$ and $0.01 \, m^2/V \cdot s$ respectively,then the semiconductor is:

Which impurity is doped in $Si$ to form an $N$-type semiconductor?

In a $P$-type semiconductor,the energy level formed in the forbidden gap near the valence band is called ...