Density of electrons in an n-type semiconductor is $10^{19} m^{-3}$. If the drift velocity is 0.02 mm/s, when an electric field $1.33 × 10^{-5}V/m$ is applied. Find the resistivity of semiconductor [contribution of holes is ignored]

0.4 Ωm

The correct answer is Option (4) → 0.4 Ωm

To calculate the Resistivity of n-type semiconductor -

(Resistivity) $ρ = \frac{1}{neμ}$

$μ$ = Mobility of electrons

$n$ = Electron Density

Also,

Drift Velocity, $v_d=μE$

$⇒μ=\frac{v_d}{E}=\frac{0.02×10^{-3}m/s}{1.33×10^{-5}V/m}=1.5×10^{-3}m^2/V.s$

$∴ρ =\frac{1}{(10^{19}m^{-3})×(1.6×10^{-19}C)×(1.5×10^{-3})}$

$=0.4Ωm$