Question

A potential barrier of $0.4V$ exists across a p-n junction. A constant electric field of magnitude ${10}^{6}V/m$ exists in the depletion region. The width of depletion region is

• A. $4\times {10}^{-7}m$
• B. $0.1m$
• C. $5\times {10}^{-7}m$
• D. None of these

Answer 1

Answer: (A)

$4\times {10}^{-7}m$

$E=\frac{V}{d}$
$d=\frac{V}{E}=\frac{0.4}{{10}^6}=0.4\times {10}^{-6}=4\times {10}^{-7}m.$