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?

Answer 1

Important consideration in the fabrication of LED: 

(a) (i) light emitting diode is a heavily doped p-n junction. 

(ii) The reverse breakdown voltages of LEDs are very low, typically around 5V. 

(b) The order of band gap of an LED to emit light in the visible range is about 3eV to 1.8eV.