AP EAMCET · PHYSICS · Semiconductors
The energy of a photon in a monochromatic light of wavelength \(621 \mathrm{~nm}\) matches with the band gap of a semiconducting material. Then the minimum energy required to create an electron-hole pair from the semiconductor is
[Take hc \(=1242 \mathrm{eV}-\mathrm{nm}\), where h is Planck's constant and \(\mathrm{c}\) is speed of light in vacuum]
- A \(3.4 \mathrm{eV}\)
- B \(1.7 \mathrm{eV}\)
- C \(2 \mathrm{eV}\)
- D \(2.2 \mathrm{eV}\)
Answer & Solution
Correct Answer
(C) \(2 \mathrm{eV}\)
Step-by-step Solution
Detailed explanation
Minimum energy required \(=\frac{1242}{621} \mathrm{eV}=2 \mathrm{eV}\)
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