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प्रश्न
Write the two processes that take place in the formation of a p-n junction.
Name two important processes involved in the formation of a p-n junction diode.
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उत्तर
The processes of "diffusion" and "drift" are critical in a p-n junction. When the p and n-sides come into contact, the majority of carriers "diffuse" from a high concentration to a low concentration. Electrons move and combine with holes from the n-side to the p-side. Holes migrate from the p-side to the n-side in the same way that electrons and holes do at the junction. A "depletion region" is formed when the near junction area runs out of carriers and becomes charged. Current "diffusion" is caused by current "diffusion."
In the depletion area, the charge produces an electric field. The electric field creates a flow of minority carriers in the 'depletion' region. The produced current is known as "drift current," and it is referred to as drift. The directions of "diffusion and drift current" are reversed.
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संबंधित प्रश्न
When a p-type impurity is doped in a semiconductor, a large number of holes are created, This does not make the semiconductor charged. But when holes diffuse from the p-side to the n-side in a p-n junction, the n-side gets positively charged. Explain.
A hole diffuses from the p-side to the n-side in a p-n junction. This means that
In a p-n junction with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the 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.
The drift current in a p-n junction is 20.0 µA. Estimate the number of electrons crossing a cross section per second in the depletion region.
Find the currents through the resistance in the circuits shown in figure.

(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
What are the readings of the ammeters A1 and A2 shown in figure. Neglect the resistance of the meters.

(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
A load resistor of 2kΩ is connected in the collector branch of an amplifier circuit using a transistor in common-emitter mode. The current gain β = 50. The input resistance of the transistor is 0.50 kΩ. If the input current is changed by 50µA. (a) by what amount does the output voltage change, (b) by what amount does the input voltage change and (c) what is the power gain?
An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?
The formation of the depletion region in a p-n junction diode is due to ______.
