Answer: Narrows (barrier reduces).
- A Widens
- B Narrows (barrier reduces)
- C Stays same
- D Disappears completely
Correct answer: B. Narrows (barrier reduces)
Explanation: Forward bias: external field opposes built-in field. Depletion region narrows. At sufficient voltage (~0.6V for Si), significant current flows.
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.