Concept:Forward bias lowers the potential barrier, allowing majority carriers to cross the junction where they become excess minority carriers and recombine.
Formula:$$\Delta n_p(x) = \Delta n_p(0) e^{-\frac{x}{L_n}} \quad (\text{Minority carrier diffusion profile})$$
Solution:- Electrons injected from the N-side cross into the P-side, where they are classified as minority carriers.
- These excess electrons diffuse through the neutral P-region away from the junction interface.
- As they diffuse, they recombine with majority holes over a characteristic minority carrier diffusion length \( L_n = \sqrt{D_n \tau_n} \).
Why other options are incorrect:- Option A: Injected carriers undergo scattering and recombination within the crystal lattice.
- Option B: Electronic transport involves valence interactions and does not alter atomic nuclei.
- Option C: Forward bias promotes carrier injection across the junction rather than repelling them back.
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