Question
Explain barrier potential of $p-n$ junction.
✓
Answer
→The loss of electrons from the $n$-region and the gain of electron by the $p$-region causes a difference of potential across the junction of the two regions.
→The polarity of this potential is such as to oppose further flow of carriers so that a condition of equilibrium exists.
→Fig. shows $p-n$ junction at equilibrium and the potential across the junction.
→Since the potential tends to prevent the movement of electron from the $n$-region into the $p$-region, it is often called a barrier potential.
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