$A$ pure $Si$ crystal has $4 \times 10^{28}$ atoms per $m^3$. It is doped with $1 \text{ ppm}$ concentration of antimony. The number of free electrons available will be

In pure silicon at $300 \ K$ temperature,the concentration of electrons $n_e$ and holes $n_h$ is $1.5 \times 10^{16} \ m^{-3}$. By doping with Indium,$n_h$ is increased to $4.5 \times 10^{22} \ m^{-3}$. Calculate the concentration of electrons $n_e$ in the doped silicon.

In a semiconductor,the number density of intrinsic charge carriers at $27^{\circ} \text{C}$ is $1.5 \times 10^{16} \, \text{m}^{-3}$. If the semiconductor is doped with impurity atoms,the hole density increases to $4.5 \times 10^{22} \, \text{m}^{-3}$. The electron density in the doped semiconductor is $..... \times 10^{9} \, \text{m}^{-3}$.

$A$ 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

When a battery is connected to a $P$-type semiconductor with a metallic wire,the current in the semiconductor (predominantly),inside the metallic wire,and inside the battery is due to which charge carriers respectively?

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