Semiconductors 2: the p-n junction (Higher Physics)

3-Second Blueprint (English)

1. Electron and hole diffusion across a p-n interface creates a carrier-free depletion layer with a built-in potential barrier.
2. Forward bias lowers the depletion energy-band slope, letting electrons and holes cross the junction and recombine once above threshold.
3. Reverse bias widens the depletion region and steepens the energy barrier, blocking majority current like an electrical insulator.