For an extrinsic semiconductor if doping concentration is increases then.

(1) For N-type and P-type fermi level will increase if T > T_{f} (T = temp of semi-conductor, T_{f} = fermi Temp.)

(2) For N-type fermi level will increase and for P-type fermi level will decrease.

(3) For N-type fermi level will decrease and for P-type fermi level will increase.

(4) For N-type fermi level will decrease and for P-type fermi level will decrease.