COMEDK · Physics · 30. Semiconductors
What is the minimum wavelength of radiation required to detect a p-n junction diode made of a semiconductor having band gap 3.3 eV.
[Planck's constant \(h = 6.6 \times 10^{34}\ J.s\)]
- A \(3300\)Å
- B \(4800\)Å
- C \(3750\)Å
- D \(7500\)Å
Answer & Solution
Correct Answer
(C) \(3750\)Å
Step-by-step Solution
Detailed explanation
For a p-n junction diode to detect radiation, the energy of the incident photon must be greater than or equal to the band gap energy of the semiconductor. \(E \ge E_g\) \(\dfrac{hc}{\lambda} \ge E_g\) \(\lambda \le \dfrac{hc}{E_g}\) The threshold wavelength is given by:…
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