When a p-n junction is reverse biased,

When a p-n junction is reverse biased, Correct Answer Depletion layer increases

CONCEPT:

• The material which is not a good conductor or a good insulator is called as semiconductor. For example: Silicon, Germanium, etc.
• The semiconductor device which is used to control the flow of electric current is called as p-n junction diode.

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• The depletion region/layer is an area at the junction where a field is formed because of formation of a negative charge layer on p side and positive charge layer on n side.

• In a p-n junction, holes from the p-side diffuse towards the n-side leaving behind the negative charges. Similarly, electrons from the n-side diffuse towards the p-side leaving behind the positive charges.
• These negative and positive charges thus formed are immobile.
• A layer of these negative and positive space-charge regions is formed. These two layers of space-charge carriers form the depletion region at the p-n junction.
• The movement of electrons from the n-side to the p-side gives rise to a potential, which prevents this movement. Hence it is termed as the barrier potential.
• Reverse bias is a situation where the n-side of the p-n junction is connected to the positive terminal of the battery.

EXPLANATION:

• In Reverse bias, the direction of the applied voltage and the barrier potential is the same.
• Due to this, the depletion layer widens as more charge carriers become immobile. So option 3 is correct.