Semiconductor Basics: Drift & Diffusion Current

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In semiconductor diodes, both drift and diffusion currents play crucial roles in charge transport. Under no bias conditions, diffusion occurs due to charge transfer, creating a depletion region that generates an electric field, leading to drift current from minority carriers. When a forward bias is applied, the battery creates an electric field, which primarily drives drift current; however, diffusion can still occur due to the concentration gradient of carriers. Some participants suggest that drift current is influenced by temperature, which affects carrier mobility and concentration. Understanding the interplay between drift and diffusion currents is essential for grasping semiconductor behavior under various bias conditions.
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My question is about drift and diffusion current.In a semiconductor diode no "bias" condition diffusion is present and due to transfer of charges due to diffusion depletion region created and then this region has ions which produce electric field which results in drift current due to force the minority charges from both the sides.So the diffusion current and after that drift current comes into picture .In forward bias there will be potential difference across the diode so there must be electric field in the diode.So in forward bias current should be due to the battery voltage .What I don't understand is ,is there any phenomenon of diffusion after applying the battery (because battery produces electric field in material,that means only drift current should be there as the drift current definition says "Drift current is the movement of electrons in electric field) ? Some says that drift current only depends on temperature (Why ?). I think don't getting the drift current what it really is . I am in really in trouble.
 
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