Is there a difference in drift and diffusion under forward biasing in a pn junction?

Question

The current in forward bias is claimed to be because of the diffusion process. 
However, from what I understand, the diffusion process is being supported by the battery by inducing fields in the direction of diffusion current itself. Thus the current we are seeing should be an imposition of drift on diffusion.

freecharly · Answer

In general, you have always a combination of drift and diffusion current in the pn-junction giving the total current in the 1-dimensional case. In the simple Shockley model for the current of the pn-junction the total current is derived only from the diffusion currents of minority carriers in the semiconductor adjacent to the depletion zone, where the electric field is assumed to be negligible. This is a good approximation due to the quasi-neutrality condition for low minority carrier injection.

Answered by freecharly on February 13, 2021

Is there a difference in drift and diffusion under forward biasing in a pn junction?

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