Write the important considerations which are to be taken into account 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?
Solution:
i) It is heavily doped p-n junction. ii) The reverse breakdown of LEDs is very low, typically around 5V. iii) The semiconductor used for fabrication of visible LEDs must at least have a band gap of 1.8eV.