why base is lightly doped

 why base is less lightly doped?

we know that Ic (collector collector) output current depend on Ie due to collector junction is reverse bias and emitter junction is forward bias(for working of transistor as an amplifier) so 99% of collector current(Ic) depend on electrons coming from emitter

                                        

                    Ie = Ib + Ic  ( for npn transistor)

                    Ic = Ie - Ib

As Ib is due of recombination of electrons from emitter with holes(present in base) in base region when electrons pass throw base region due to this recombination the electrons entering into collector will decrease.so to have less recombination we dope the base lightly so that less recombination occur and we can get high collector current(Ic)

Thanks for reading the article.