Question
Which currents are produced when an external electric field is applied on a semi-conductor?

Answer

When an external electric field is applied on a semiconductor, the charge carriers produce two types of currents :
(1) Drain current : This current flows from the external electric field of charge carriers. It arises as a result of movement along.
(2) Diffusion current : This current arises due to the movement of free charge carriers in a semiconductor from high concentration region to low concentration region.

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