wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Describe briefly , with the help of a diagram, the role of the two important processes involved in the formation of a pn junction.

Open in App
Solution

The two important process involved in formation of p - n junction:
(i) Diffusion
(ii) Drift
When p and n sides comes in contact then majority carries diffuse from high concentration to low concentration. Electrons flow from n to p junction and combines with holes near the junction. Similarly holes flow from p-side to n side and combine with electrons near the junction. As this happens, region near the junction gets depleted of carriers and gets charged as shown in figure. This diffusion of carriers leads to diffusion current.
The charge in depletion region creates electric field. This electric field leads to flow of minority carriers across depletion region. This is called the drift current.
The diffusion and drift currents are opposite in direction.
In equilibrium, they are equal to each other and p-n junction is formed.

1681296_1392727_ans_9194a24961dd4e5997a0cd5f863ffc42.jpg

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
PN Junction
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon