Pure Silicon crystal at $300 \mathrm{~K}$ has equal electron and hole concentration of $1.5 imes 10^{16} \mathrm{~m}^{-3}$. Doping by indium increases $n_h=4.5 imes 10^{22} \mathrm{~m}^{-3}$. The $n_e$ in the doped silicon is:

Question

Pure Silicon crystal at $300 \mathrm{~K}$ has equal electron and hole concentration of $1.5 	imes 10^{16} \mathrm{~m}^{-3}$. Doping by indium increases $n_h=4.5 	imes 10^{22} \mathrm{~m}^{-3}$. The $n_e$ in the doped silicon is:

Aicharya · Accepted Answer

In an extrinsic semiconductor: $\begin{aligned} & n_e n_h=\left(n_iight)^2 \ & n_e 	imes 4.5 	imes 10^{22}=\left(1.5 	imes 10^{16}ight)^2 \ & n_e=\frac{2.25 	imes 10^{32}}{4.4 	imes 10^{22}} \ & 	herefore n_e=5 	imes 10^9\end{aligned}$ .

Pure Silicon crystal at $300 \mathrm{~K}$ has equal electron and hole concentration of $1.5 \times 10^{16}…

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