0
Why charge carriers are not present in depletion region of am pn junction?
Wiki User
∙ 13y ago
depletion region is formed only after recombination of holes and electrons..so in depletion region there are only and only immoble positive and nagative ions...hence,there is no charge carrier..
Wiki User
∙ 13y ago
Add your answer:
Earn +20 pts
Why potential across pn junction is called potential barrier?
The potential across a pn junction is called potential barrier because majority charge carriers have to overcome this potential before crossing the junction.
Why depletion region in pn junction is called depletion region?
because charge carriers are depleted there, some electrons from n side have fallen into holes on p side reducing/depleting carriers on both sides.
Why the depletion layer becomes very thick when then pn junction diode is lightly doped?
When the pn junction is forward biased,the height of the potential barrier is reduced allowing more majority charge carriers ti flow across the junction and when it is reversed biased, the height of the potential barrier increases there b reducing the majority charge carrier that have sufficient energy to flow across the junction.
What is the depletion layer in a semi conductor?
in correct sense it is not the layer but the region around the metallurgical junction which is depleted of charge carriers .in this region an internal electric field exist which counter balance the diffusion of electron and hole around the junction . basically the main reason for the formation of depletion region is the concentration gradient across metallurgical junction of p-n semiconductor.
What is depletion region in a diode?
As we bring P type and N type semiconductors fused together, then rich holes in P type would get neutralized with some rich electrons in N type. Hence at the juntion region, there will not be charge carriers ie holes and electrons. So it is known as Depletion Region. Depletion means emptying something. In case of ordinary diode this depletion region would be wider where as in case of Zener Diode the depletion region would be narrower. This is because the semiconductors are heavily doped. Hence potential barrier would be easily built up even with a thin region where holes and electrons get combined for neutrelization.
How do you control PN-junction?
When a pn junction is direct polarized, the height of the depletion layer is reduced and majority charge carriers now have sufficient energy to cross the junction and when it is revers polarized the height of the depletion layer is increased and the number of majority charge with sufficient energy to cross the junction is cut sharply.
What causes depletion region across P-N junction?
The presence of mobile and bound charges on either sides of the pn junction causes the depletion layer. A pn junction is formed when a semiconductor is dopped with a pentavalent impurity on one side and a tri-valent impurity on the other side.on one side electrons will be more in number and on the other side holes will be more in number.At the junction the electrons combine with holes and there will be no charge carriers(i.e. electrons and holes) in that region.That region which is free from charge carriers is called depletion region.
Why potential across pn junction is called potential barrier?
The potential across a pn junction is called potential barrier because majority charge carriers have to overcome this potential before crossing the junction.
Why depletion region in pn junction is called depletion region?
because charge carriers are depleted there, some electrons from n side have fallen into holes on p side reducing/depleting carriers on both sides.
Why the depletion layer becomes very thick when then pn junction diode is lightly doped?
When the pn junction is forward biased,the height of the potential barrier is reduced allowing more majority charge carriers ti flow across the junction and when it is reversed biased, the height of the potential barrier increases there b reducing the majority charge carrier that have sufficient energy to flow across the junction.
What is the depletion layer in a semi conductor?
in correct sense it is not the layer but the region around the metallurgical junction which is depleted of charge carriers .in this region an internal electric field exist which counter balance the diffusion of electron and hole around the junction . basically the main reason for the formation of depletion region is the concentration gradient across metallurgical junction of p-n semiconductor.
What is depletion region in a diode?
As we bring P type and N type semiconductors fused together, then rich holes in P type would get neutralized with some rich electrons in N type. Hence at the juntion region, there will not be charge carriers ie holes and electrons. So it is known as Depletion Region. Depletion means emptying something. In case of ordinary diode this depletion region would be wider where as in case of Zener Diode the depletion region would be narrower. This is because the semiconductors are heavily doped. Hence potential barrier would be easily built up even with a thin region where holes and electrons get combined for neutrelization.
What is space charge region in pn junction?
The depletion region is also called as the space charge region.A p-n junction diode is formed by placing p and n type semiconductor materials in intimate contact on an atomic scale. This may be achieved by diffusing acceptor impurities into an n type silicon crystal or by the opposite sequence.In an open circuit p-n junction diode, majority carriers from either side will diffuse across the junction to the opposite side where they are in minority. These diffusing carriers will leave behind a region of ionized atoms at the immediate vicinity of the metallurgical junction. This region of immobile ionized atoms is called the space charge region.
How depletion region is narrowed during forward biasing?
When the pn junction is forward biased, some of the space charge is neutralized reducing the width of the pn junction.
Why collector base junction is always reverse biased for normal operation of transistors?
collector junction is reverse biased so as to remove the charge carriers away from its junction with the base.
Why emitter is always forward biased with respect to base?
It is because the emitter is the source of charge carriers and we require to move these charge carriers into base which is obtained only by forward baising the base emitter junction.
What is depletion layer?
a layer that is present b/w the positive and negative charge
