Question

The width of depletion region in a p–n junction diode is 500 nm and an intense electric field of 6×10⁵ V/m is also found to exist. The height of potential barrier is 

(1) 0.30 V 

(2) 0.40 V 

(3) 3 V

(4) 4 V

Answer 1

Correct option: (1) 0.30 V

Explanation: 

Let V be potential barrier across depletion layer of width d. E the electric field in the |E| = V/d or V = |E|.d

∴ V = 6 × 10⁵ × 500 × 10^–9 

= 0.30 V