Question

Select the correct statement from the following:
A) emitter is lightly doped
B) collectors’ thickness is less than that of emitter
C) base is very lightly doped
D) transistor is a two-terminal device.

Answer 1

In a transistor, find out the work done by the emitter, base and collector and check where most of the current carriers will be present. It consists of an emitter, base, and collector as its input terminals and two junctions.

Complete answer:
A transistor is a semiconductor device which is used to amplify or switch electronics signals and electric power. It consists of two junctions and three terminals. The three terminals are emitter, base and collector. In the three terminals, the emitter is the most heavily doped, followed by collector which is moderately doped and base, which is lightly doped of all the three terminals. Option a is wrong. Next, the thickness of base is usually less than the emitter and the collector in order to get minimum current in the base or to not let the charge dissipate in the base. Option b is also wrong.
In the three terminals we have, the base is lightly doped so that it can pass most of the emitter injected electrons to the collector. Therefore, option c is correct. A transistor consists of three terminals, so option d is wrong.

So, the correct answer is “Option C”.

Additional Information:
Emitter is heavily doped because it sends or injects the electrons into the base. A transistor can work either as a switch or an amplifier. In an amplifier, it takes a small amount of current in one side and produces a much bigger amount at the other end. These were first used to prepare hearing aids. A transistor can also work as switches, they can store two different numbers at once as a switch. These are used in computers in billions in numbers.

Note:
The doping measurement goes in increasing level as, emitter greater than collector greater than the base. Most of us assume the collector as the least doped one, but the base is the one that is least doped so as to send all the electrons ejected by emitter to the collector.