In n type semiconductors one electron is in excess so why movement of that electron to conduction band creates a hole in valence band?

Dear student,

In n-type semiconductor pentavalent impurities are added to the parent material(Si),four of its electrons bond with the four silicon neighbours while the fifth remains very weakly bound to its parent atom.This free electron will be free to move in the lattice of the semiconductor even at room temperature and movement of this electron does not create any hole because theoretically no bond is breaking.

Regards,
Gaurav kumar gupta
In house expert- physics
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