The depletion layers in a p-n junction diode consists of layers of :a)...
The depletion layer in p-n junction consists of the layer of positively charged donors on the n-side and negatively charged acceptors on p-side.
The correct answer is: Positively charged donors on the n-side and negatively charged acceptors on the p-side
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The depletion layers in a p-n junction diode consists of layers of :a)...
Depletion Layers in a p-n Junction Diode
The depletion layer is a region in a p-n junction diode where the mobile charge carriers are depleted, resulting in the formation of a potential barrier. This barrier prevents the flow of current in the reverse biased direction and allows current to flow freely in the forward biased direction. The correct answer to this question is option 'C', which states that the depletion layers consist of positively charged donors on the n-side and negatively charged acceptors on the p-side.
Explanation:
To understand why option 'C' is correct, let's break down the formation of the depletion layer in a p-n junction diode:
1. P-N Junction Formation: A p-n junction diode is formed by bringing together a p-type semiconductor (which has an excess of positively charged holes) and an n-type semiconductor (which has an excess of negatively charged electrons). When these two regions come into contact, electrons from the n-side diffuse to the p-side and recombine with the holes, leading to the formation of a depletion region.
2. Depletion Region Formation: As electrons diffuse from the n-side to the p-side, they leave behind positively charged donor ions on the n-side. Similarly, the holes diffusing from the p-side to the n-side leave behind negatively charged acceptor ions on the p-side. This separation of charges creates an electric field that opposes further diffusion of charge carriers, resulting in the formation of the depletion region.
3. Barrier Potential: The separation of charges in the depletion region creates an electric field that gives rise to a potential difference across the junction. This potential difference is called the barrier potential, and it prevents the flow of current in the reverse biased direction. The barrier potential depends on the concentration of donor and acceptor ions in the depletion region.
4. Depletion Layer Characteristics: The depletion layer is an insulating region with no mobile charge carriers. It is relatively thin and has a high resistivity compared to the p and n regions of the diode. The width of the depletion layer depends on the doping concentrations of the p and n regions.
5. Electric Field: Within the depletion layer, there is an electric field directed from the positive side (p-side) to the negative side (n-side). This electric field is responsible for repelling any further movement of charge carriers across the junction.
In summary, the depletion layers in a p-n junction diode consist of positively charged donor ions on the n-side and negatively charged acceptor ions on the p-side. This charge separation creates a potential barrier that allows the diode to function as a one-way current device.