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Question
Explain briefly with the help of necessary diagrams, the reverse biasing of a p-n junction diode. Also draw characteristic curves.
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Solution
p-n junction diode under reverse bias
Positive terminal of battery is connected to n-side and negative terminal to p-side.
Reverse bias supports the potential barrier. Therefore, the barrier height increases and the width of depletion region also increases.
Effective barrier height under reverse bias is (V0 + V).
No conduction across the junction due to majority carriers; few minority carriers cross the junction after being accelerated by high reverse bias voltage
This constitutes a current that flows in opposite direction − celled reverse current.
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