A semiconductor has equal electron and holc concentration of $6 imes 10^8$ per $\mathrm{m}^3$. On

Question

A semiconductor has equal electron and holc concentration of $6 	imes 10^8$ per $\mathrm{m}^3$. On doping with certain impurity. electron concentration increases to $9 	imes 10^{12}$ per $\mathrm{m}^3$. The new hole concentration is

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(c): As, $n_e n_h=n_i^2$\ Here, $n_i=6 	imes 10^8$ per $\mathrm{m}^3$ and $n_e=9 	imes 10^{12}$ per $\mathrm{m}^3$ \ $ 	herefore \quad n_h=\frac{n_i^2}{n_e}=\frac{\left(6 	imes 10^8ight)^2}{9 	imes 10^{12}}=4 	imes 10^4 	ext { per } \mathrm{m}^3 $