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Semiconductors and Semiconductor Devices — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsSemiconductors and Semiconductor Devices3 Marks
Question
The drift current in a reverse-biased p-n junction increases in magnitude if the temperatu,re of the junction is increased. Explain this on the basis of creation of hole-electron pairs.
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Answer

When the temperature of a reverse-biassed p‒n junction is increased, the breaking of bonds takes place because of the increase in the thermal energy of the charge carriers. Drift current is due to the flow of the minority carriers across the junction. So, when a p‒n junction is reverse biassed, the applied voltage supports the flow of minority charge carriers across the junction. Thus, the drift current increases with increase in temperature in a reverse biassed p‒n junction.

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