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If P-N junction diode is in reverse bias, then:

If P-N junction diode is in reverse bias, then: Correct Answer The direction of applied voltage is same as the direction of barrier potential

CONCEPT:

Diode:

  • A diode is a semiconductor device that essentially acts as a one-way switch for current.
    • It allows current to flow easily in one direction but severely restricts current from flowing in the opposite direction.

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  • Forward bias and reverse bias:

 

Forward bias Reverse bias
In the forward bias, the p side of the diode is connected to the positive side of the battery and the n side is connected to the negative side of the battery.  When the p-side is connected to the negative terminal and the n-side is connected to the positive terminal of the battery, it is called reverse biased. 
The direction of the applied voltage is opposite to the junction barrier potential. Therefore, the size of the depletion region decreases. When a reverse bias is applied, free electrons are pulled away from the junction, which results in the increase of the width and resistance of the depletion region.


EXPLANATION:

Reverse bias:

  • When an external voltage (V ) is applied across the diode such that the n-side is positive and the p-side is negative, it is said to be reverse biased. The applied voltage mostly drops across the depletion region.
  • The direction of the applied voltage is the same as the direction of barrier potential. As a result, the barrier height increases, and the depletion region widens due to the change in the electric field. Hence, option 1 is correct.

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