Asked by SAGAR | 14th Feb, 2012, 04:07: PM

Expert Answer:

The Emitter is highly doped because all the free charges (  conduction electrons in Ntype and holes in P type) starts from Emitter. Base is lightly doped because we want that the base current should be small.Now the collector is moderately doped may be because we dont want  a crowd of electrons in the collector otherwise the electrons coming from the Emitter-Base path may repelled and collector current may decrease. 

Answered by  | 14th Feb, 2012, 07:32: PM

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