Assertion: A p-n junction with reverse bias c | vedclass

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(A) photo-diode is a reverse-biased $p-n$ junction diode. At the $p-n$ junction,there exists a junction electric field which,at equilibrium,does not p

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(A) photo-diode is a reverse-biased $p-n$ junction diode. At the $p-n$ junction,there exists a junction electric field which,at equilibrium,does not permit the flow of charge carriers across the junction.When such a $p-n$ diode is illuminated with light photons having energy $h
u > E_{g}$,electron-hole pairs are generated in the depletion layer (or near the junction). These charge carriers are separated by the junction field and made to flow across the junction,resulting in a change in the reverse saturation current.Because the reverse current is highly sensitive to the generation of these photo-excited carriers,the change in current is directly proportional to the incident light intensity. Thus,the device acts as a photo-detector.

Assertion: $A$ $p-n$ junction with reverse bias can be used as a photo-diode to measure light intensity.
Reason: In a reverse bias condition,the current is small but is more sensitive to changes in incident light intensity.

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Assertion: $A$ $p-n$ junction with reverse bias can be used as a photo-diode to measure light intensity.Reason: In a reverse bias condition,the current is small but is more sensitive to changes in incident light intensity.