Question

what do you know about a pn junction diode.​

Answer 1

Explanation:

• Made by forming close contact of a n-type and a p-type semiconductor, forming there junction at between (hence the name).
• Formation of depletion layer takes place in between, where electrons diffuses from n side to p side and holes the other way around.
• Because of the depletion layer, the current moves easily when p side is connected to positive terminal of source and n type to negative, as doing so depletion layer becomes thin and majority charge carriers from both side help in conducting electricity (This is called forward bias). However initially potential takes time to increase, and shoots when the potential barrier (potential difference due to depletion layer) is overcome.
• Similarly, current hardly flows from when n side is connected to positive terminal and p side to negative, as then depletion layer becomes thick and only minority charge carriers from both the sides conduct somewhat current. (This is called reverse bias). However too much potential and the crystal lattice might break (a.k.a Avalanche Breakdown).
• Because of this property, current only flows in one direction, which is helpful in devices such as Rectifiers, Solar Cells, etc.

Answer 2

Hope it helps...

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