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

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(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

Vedclass · Accepted Answer

If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

Vedclass · Answer

(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 $hu > E_{g}$,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.

Similar Questions

Identify the correct circuit diagrams for the normal operation from the following.

An $LED$ (Light Emitting Diode) is constructed from a $p-n$ junction based on a certain $Ga-As-P$ semiconducting material whose energy gap is $1.9\, eV$. What is the wavelength of the emitted light?

Consider the following statements $A$ and $B$ and identify the correct answer:
$A$. For a solar-cell,the $I-V$ characteristics lies in the $IV$ quadrant of the given graph.
$B$. In a reverse biased $pn$ junction diode,the current measured in $(\mu A)$ is due to majority charge carriers.

Which type of semiconductor device does not need any bias voltage?

When light shines on a $p-n$ junction diode,the current $I$ versus voltage $V$ is observed as in the figure below. In which quadrant$(s)$ does the diode generate power,so that it can be used as a solar cell?

Vedclass Test Series

Exam Paper Generator

Online Exam Module

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.