Question
Mention the important considerations required while fabricating a p-n junction diode to be used as a Light Emitting Diode (LED). What should be the order of band gap of an LED if it is required to emit light in the visible range?
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Answer
- It is a heavily doped p-n junction.
- The reverse breakdown voltages of LEDs are very low.
- The semiconductor used for fabrication of visible LEDs must atleast have a band gap of 1.8 eV.
Order of band gap is about 3 eV to 1.8 eV.
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