Question

A transistor has three impurity regions , emitter , base and collector. Arrange them in order of increasing doping levels.

Answer 1

In increasing level of doping

Base < Collector< Emitter

•Transistor is a three terminal device which transfers a signal from low resistance circuit to high resistance circuit.

Each transistor has three terminals

i) Emitter

ii) Base

iii) Collector

•Emitter : It is the left most part of the transistor . It emits majority carriers towards base . It is highly doped & medium in size

•Base : It is the middle part of transistor . It is lightly doped & very thin in size

•Collector : It is the right side part of the transistor. It collects the majority carriers which are emitted by the emitter. It has large size & is moderately dopped.

•So, in increasing level of doping

Base < Collector< Emitter