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प्रश्न
In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.
पर्याय
free electrons in the n-region attract them.
they move across the junction by the potential difference.
hole concentration in p-region is more as compared to n-region.
All the above.
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उत्तर
Hole concentration in p-region is more as compared to n-region.
Explanation:
The diffusion of charge carriers across a junction takes place from the region of higher concentration to the region of lower concentration. In this case, the p-region has a greater concentration of holes than the n-region. Hence, in an unbiased p-n junction, holes diffuse from the p-region to the n-region.
संबंधित प्रश्न
In a p-n junction diode, the current I can be expressed as
I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`
where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then
(a) What will be the forward current at a forward voltage of 0.6 V?
(b) What will be the increase in the current if the voltage across the diode is increased to 0.7 V?
(c) What is the dynamic resistance?
(d) What will be the current if reverse bias voltage changes from 1 V to 2 V?
Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.
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The drift current in a p-n junction is
The diffusion current in a p-n junction is
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(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
Draw the current-voltage characteristics for the device show in figure between the terminals A and B.
(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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