Q5 of 50 Page 1

Name the type of semiconductor obtained when silicon is doped with boron.

Since boron contains only three electrons in the outermost shell, when semiconductor like silicon is doped with boron, the three electrons form pairing with the three electrons of silicon and the remaining one electron of silicon remains unpaired. This creates a vacancy or hole.

Hence doping a semiconductor with boron or aluminium forms a P-type semiconductor with the majority carriers as hole.


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