Question

Explain the importance of the depletion region in a p-n junction diode.

Answer 1

Dear Student,. Depletion region is the region at the junction of p-type and n- type region which is depleted from charge carriers. This leads to the development of barrier potential across it. This breakdown voltage is 0.7 V (for So diodes) and 0.3 V (for Ge diodes) when forward biased and is equal to the applied potential when reverse biased. The Depletion region shrinks to a minimum width when forward biased and expands gradually when reverse biased. Due to this nature of the Depletion region, a p n junction allows current due to majority carriers along one direction while only allows small current due to minority carriers along the other. So, it behaves like a one way switch. Regards