The depletion region and the built-in barrier
Electrical Technology · Grade 10 · about 40 minutes
The middle of a PN junction has no free carriers, an internal field, and a barrier of about 0.7 V in silicon.
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- 7 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
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Other lessons in this sub-strand
- Semiconductor theory
- Conductors, insulators and semiconductors
- Why silicon is the electronics material
- The silicon atom and the crystal lattice
- Covalent bonds in pure silicon
- Intrinsic semiconductors and electron-hole pairs
- Doping: making extrinsic semiconductors
- N-type semiconductors
- P-type semiconductors
- Majority and minority carriers
- Simulating covalent bonding in extrinsic silicon
- Comparing N-type and P-type silicon
- How a PN junction forms
- The depletion region and the built-in barrier
- Why semiconductors matter in electronics