Pure Si at $500 \mathrm{~K}$ has equal number of electron $\left(n_e ight)$ and hole $\left(n_h ight)$ concentrations of $1.5 imes 10^{16} \mathrm{~m}^{-3}$. Doping by indium increases $n_h$ to $4.5 imes 10^{22} \mathrm{~m}^{-3}$. The doped semiconductor is of

Question

Pure Si at $500 \mathrm{~K}$ has equal number of electron $\left(n_eight)$ and hole $\left(n_hight)$ concentrations of $1.5 	imes 10^{16} \mathrm{~m}^{-3}$. Doping by indium increases $n_h$ to $4.5 	imes 10^{22} \mathrm{~m}^{-3}$. The doped semiconductor is of

Aicharya · Accepted Answer

$\begin{aligned} & n_i^2=n_e n_h \ & n_e=\frac{\left(n_iight)^2}{n_h} \ & n_e=\frac{\left(1.5 	imes 10^{16}ight)^2}{\left(4.5 	imes 10^{22}ight)} \ & n_e=5 	imes 10^9 \mathrm{~m}^{-3} \end{aligned}$ So, $n_{h} \gg n_e$ semiconductor is $p$-type.

Pure Si at $500 \mathrm{~K}$ has equal number of electron $\left(n_e\right)$ and hole $\left(n_h\right)$…

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