Advertisements
Advertisements
प्रश्न
Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.
Advertisements
उत्तर
p-n junction diode under forward bias
p-side is connected to positive terminal and n-side to the negative terminal.
Applied voltage drops across the depletion region.
Direction of applied voltage (V) is opposite to the build in potential (V0).
As the depletion layer width decreases, the barrier height is reduced.
Effective barrier height under forward bias is (V0 − V).
-
Electron in n-region moves towards the p-n junction and holes in p-region move towards the junction. The width of the depletion layer decreases and hence, it offers less resistance.
-
Diffusion of majority carriers takes place across the junction.
This leads to forward current.
APPEARS IN
संबंधित प्रश्न
Mention the important considerations required while fabricating a p-n junction diode to be used as a Light Emitting Diode (LED). What should be the order of band gap of an LED if it is required to emit light in the visible range?
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.
Two identical p-n junction may be connected in series with a battery in three ways. The potential difference across the two p-n junctions are equal in
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.
In a p-n junction,
(a) new holes and conduction electrons are produced continuously throughout the material
(b) new holes and conduction electrons are produced continuously throughout the material except in the depletion region
(c) holes and conduction electrons recombine continuously throughout the material
(d) holes and conduction electrons recombine continuously throughout the material except in the depletion region.
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.
Consider a p-n junction diode having the characteristic \[i - i_0 ( e^{eV/kT} - 1) \text{ where } i_0 = 20\mu A\] . The diode is operated at T = 300 K . (a) Find the current through the diode when a voltage of 300 mV is applied across it in forward bias. (b) At what voltage does the current double?
Choose the correct option.
Current through a reverse-biased p-n junction increases abruptly at:
In a semiconductor diode, the barrier potential offers opposition to only ______.
For an ideal diode, in forward and reverse biased condition the resistance is respectively ______.
