In a good conductor,the energy gap between the conduction band and the valence band is:

Explain by drawing the energy levels of $Si$ and $Ge$ containing $N$ atoms at $0\, K$ temperature.

Carbon, silicon, and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by $(E_g)_C$, $(E_g)_{Si}$, and $(E_g)_{Ge}$ respectively. Which one of the following relationships is true in their case?

The energy gap of silicon is $1.1 \, eV$. At what wavelength will silicon stop absorbing photons? (in $\mathring A$)

The relation between the number of free electrons in semiconductors $(n)$ and its temperature $(T)$ is

The band gap in Germanium and Silicon in $eV$ respectively is