Question
Write any two distinguishing features between conductors, semiconductors and insulators on the basis of energy band diagrams.
✓
Answer
Two distinguishing features:
- In conductors, the valency band and conduction band tend to overlap (or nearly overlap) while in insulators they are seperated by a large energy gap and in semiconductors are separated by a small energy gap.
- The conduction band, of a conductor, has a large number of electrons available for electrical conduction. However the conduction band of insulators is almost empty while that of the semi- conductor has only a (very) small number of such electrons available lectrical conduction.
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