Question

$\text{An n-type semiconductor sample is doped with}{10}^{15}{\text{donor atoms/cm}}^3{\text{. The applied electric field is 1V/cm. If the current density produced inside the sample is 60 mA/cm}}^2\text{. Then the mobility of the electrons inside the n-type sample is}$

• A. $200c{m}^2/V-sec$
• B. $312c{m}^2/V-sec$
• C. $187.5c{m}^2/V-sec$
• D. $375c{m}^2/V-sec$

Answer 1

The correct option is D $375c{m}^2/V-sec$

Ans : (d)

$\text{Given,}{N}_D={10}^{15}atom/c{m}^3$
$E=1V/cm$
$J=60mA/c{m}^2$
$\text{Current density,}J=\sigma E$
$\text{Conductivity}=\sigma =nq{\mu }_n$
$\therefore nq{\mu }_u=\frac{J}{E}$
$\therefore {\mu }_n=\frac{J}{nqE}=\frac{60\times {10}^{-3}}{{10}^{15}\times 1.6\times {10}^{-19}\times 1}$
$\therefore {\mu }_u=375c{m}^2/V-sec$