In a junction diode,the holes are due to

$A$ $P$-type semiconductor has acceptor levels $57 \; meV$ above the valence band. The maximum wavelength of light required to create a hole is (Planck's constant $h = 6.6 \times 10^{-34} \; J \cdot s$, speed of light $c = 3 \times 10^8 \; m/s$)

Let ${n_h}$ and ${n_e}$ be the number of holes and conduction electrons respectively in a semiconductor. Then

The mobility of free electrons is greater than that of free holes because

$A$ 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

Which of the following dopants is used in germanium to form an $n$-type semiconductor?