These are obtained by adding a small amount of trivalent impurity to a pure sample of semiconductor (Ge).
Majority charge carriers — holes
Minority charge carriers — electrons
- Conductivity σ » nh µh e
- P-type semiconductor is also electrically neutral (not positively charged).
- Impurity is called Acceptor impurity.
- Acceptor energy level lies just above the valence band.
Conductivity of Semiconductor
(1) In intrinsic semiconductors ne = nh.
(2) When some potential difference is applied across a piece of intrinsic semiconductor current flows in
it due to both electron and holes.
i= ie+ih Þ i =eA[neve+nhvh]