PN junction with different doping concentrations

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Thread Starter


Joined Dec 31, 1969
I have difficulty in understanding the BJT working
It led me to the doubt

Suppose if there is a PN junction diode with N heavily doped and P lightly doped and thiner than the N region say..
and we supply a forward bias voltage to it..

What will happen:

Will the heavily doped N inject more amount of electrons in the P region in exchange for the fewer holes from the P side..
Will the N region inject exactly the amount of electrons equal to the holes from the P region..

My intuition says the second one is right, but while understanding the BJT all authors state that since since the base is lightly doped it is very easy for the emitter to flood it with electrons and the excess electrons will pass through the collector...

Can anyone help with the case of PN junction diode and relate it with BJT


Joined Mar 24, 2008
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