MCQ
The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480 \;nm$ is incident on it. The band gap in $(eV)$ for the semiconductor is
- A$0.9$
- B$0.7$
- ✓$0.5$
- D$1.1$
✓
Answer
Correct option: C.
$0.5$
c
$E_{g}=h v$
$E_{g}=h v$
$=\frac{h c}{\lambda}=\left(\frac{6.63 \times 10^{-34} \times 3 \times 10^{8}}{2480 \times 10^{-9} \times 1.6 \times 10^{-19}}\right) eV$
$=0.5 eV$
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