Question

Calculate the resistivity of an n-type semiconductivity from the following data: density of conduction electrons = $8\times {10}^{13}c{m}^{-3}$, density of holes $=5\times {10}^{12}c{m}^{-3}$, mobility of conduction electron in $=2.3\times {10}^{4}c{m}^2{V}^{-1}{s}^{-1}$ and mobility of holes $=100c{m}^2{V}^{-1}{s}^{-1}$.

Answer 1

Resistivity of a semiconductor is given by:

$\rho =\frac{1}{\sigma }=\frac{1}{e(n{\mu }_n+p{\mu }_p)}$

$=\frac{1}{1.6\times {10}^{-19}(8\times {10}^{13}\times {10}^6\times 2.3\times {10}^4\times {10}^{-4}+5\times {10}^{12}\times {10}^6\times 100\times {10}^{-4})}$

$=\frac{1}{1.6\times (18.4+.005)}$

$\approx 0.034\Omega m$