In a p−n junction diffusion occurs due to spontaneous movement of majority charge carrier from the region of high concentration to low concentration.
JEE Main 2015 — Physics Modern Physics
In an unbiased p - n junction electrons diffuse from n-region to p-region because:
Held on 10 Apr 2015 · Verified 6 Jul 2026.
electrons travel across the junction due to potential difference
only electrons move from n to p region and not the vice - versa
electron concentration in n - region is more as compared to that in p - region
holes in p - region attract them
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