In a p-n junction, the depletion region is 400 nm wide and an electric field of 5×105 V m−1 exists in it. (a) Find the height of the potential barrier. (b) What should be the minimum kinetic energy of a conduction electron which can diffuse from the n-side to the p-side ?
Depletion region 'd'
=400 nm=4×10−7 m
(a) Potential barrier 'V'
=E×d=5×d
(b) Kinetic Energy required
∴ Potential barrier ×e=0.2 eV.
[Where 'e' = Orange of electron]