Answer: Negative for Zener ( 7V).
- A Always positive, regardless of the underlying breakdown mechanism
- B Negative for Zener (<5V), positive for avalanche (>7V)
- C Exactly zero, with the breakdown voltage independent of temperature
- D Independent of mechanism, with Zener and avalanche behaving identically
Correct answer: B. Negative for Zener (<5V), positive for avalanche (>7V)
Explanation: Zener (<5-6V): tunneling, negative TC. Avalanche (>7V): ionization, positive TC. At ~5.6V: compensate for near-zero TC in reference diodes.
Conductors have overlapping bands, semiconductors have a small energy gap that can be bridged by heat or doping, and insulators have a large gap that blocks conduction.
Concept context
Band theory, p-n junction, diodes, transistors, logic gates, and integrated circuits.