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प्रश्न
The drift current in a p-n junction is
विकल्प
from the n-side to the p-side
from the p-side to the n-side
from the p-side to the side if the junction is forward-biased and the opposite direction if it is reverse-biased
from the p-side to the n-side if the junction is forward-baised and in the opposite direction if it is reverse-biased.
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उत्तर
from the n-side to the p-side
After the diffusion of majority charge carriers across a p‒n junction, an electric field is set up because of the accumulation of immobile ions at the junction. These further oppose the motion of majority charge carriers across the junction. As a result, electrons from the p region start moving to the n region and holes from the n region start moving to the p region. This constitutes the drift current. As the direction of the current is opposite to the direction of the motion of the electrons, the direction of the drift current is from the n side to the p side.
In forward biasing, there is no movement of electrons from the p region to the n region and of holes from the n region to the p region. Hence, there is not drift current.
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संबंधित प्रश्न
In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.
A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?
Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.
How is a zener diode fabricated so as to make it a special purpose diode? Draw I-V characteristics of zener diode and explain the significance of breakdown voltage.
Explain briefly, with the help of a circuit diagram, how a p-n junction diode works as a half wave rectifier.
A semiconducting device is connected in a series circuit with a battery and a resistance. A current is found to pass through the circuit. If the polarity of the battery is reversed, the current drops to almost zero. the device may be
(a) an intrinsic semiconductor
(b) a p-type semiconductor
(c) an n-type semiconductor
(d) a p-n junction
When a p-n junction is reverse-biased, the current becomes almost constant at 25 µA. When it is forward-biased at 200 mV, a current of 75 µA is obtained. Find the magnitude of diffusion current when the diode is
(a) unbiased,
(b) reverse-biased at 200 mV and
(c) forward-biased at 200 mV.
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Find the current through the resistance R in figure if (a) R = 12Ω (b) R = 48Ω.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Zener breakdown occurs in a p-n junction having p and n both:
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In p-n junction diode ______.
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What is a p-n junction diode?
Which charge carriers remain near the junction after the region loses mobile charge carriers?
How does the interface between physically joined p-type and n-type slabs act on charge carriers?
How is a true p-n junction created instead of physically joining separate semiconductor pieces?
Which semiconductor devices use the p-n junction principle?
What is the approximate knee voltage for germanium?
