CBSE Class 12 · SemiconductorsShort Answer

Draw the energy band diagram for an n-type and a p-type semiconductor at

T > 0 K

Solution

For an n-type semiconductor at

T > 0 K

, pentavalent donors create a donor level just below the conduction band; at finite temperature these electrons are excited into the conduction band.
For a p-type semiconductor, trivalent acceptors create an acceptor level just above the valence band; valence electrons move up into it, leaving holes in the valence band.

n-type: donor level below CB; p-type: acceptor level above VB.

CBSE Class 12 Board · Subjective

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