JEE Mains · Physics · STD 12 - 14. Semicondutor electronics
Consider a situation in which reverse biased current of a particular \(P-N\) junction increases when it is exposed to a light of wavelength \(\le 621\, {nm}\). During this process, enhancement in carrier concentration takes place due to generation of hole-electron pairs. The value of band gap is nearly. (In \({eV}\))
- A \(1\)
- B \(4\)
- C \(2\)
- D \(0.5\)
Answer & Solution
Correct Answer
(C) \(2\)
Step-by-step Solution
Detailed explanation
Band gap \(=\frac{h c}{\lambda_{0}}\) Where \(\lambda_{0}=\) threshold wavelength Band gap \(=\frac{1242\, {ev}-\,{nm}}{621\, {nm}}=2\, {ev}\)
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