Question

The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480nm$ is incident on it. The band gap (in $eV$) for the semiconductor is

• A. $0.9$
• B. $0.7$
• C. $0.5$
• D. $1.1$

Answer 1

The correct option is C $0.5$

Band gap, $E_g=\frac{hc}{\lambda }=\frac{(6.63\times {10}^{-34})(3\times {10}^8)}{2480\times {10}^{-9}\times 1.6\times {10}^{-19}}eV=0.5eV$