Raising the doping concentration in a crystal diode causes its breakdown voltage to __________________?
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Answer: C. is decreased
Explanation
Higher doping concentration decreases the depletion layer width, which lowers the reverse breakdown voltage of a crystal diode. Adding more impurity atoms packs the semiconductor lattice tightly, intensifying electric fields across the narrow junction barrier. This intense electric field allows avalanche or Zener breakdown to occur at much lower reverse voltage values. Doping involves intentionally adding impurity atoms into semiconductor silicon or germanium to alter its electrical conduction properties. The depletion region width is inversely proportional to the square root of the semiconductor doping concentration levels. Zener diodes are heavily doped specifically to achieve sharp, low voltage reverse breakdown characteristics for circuit regulation.
Remaining the same ignores the fundamental physics relationship between semiconductor doping levels and depletion region widths. An increased breakdown voltage contradicts semiconductor physics, as heavier doping actually narrows depletion regions and lowers breakdown. None of the above is incorrect because the breakdown voltage definitely decreases when doping concentration is raised.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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