Question

The part of the transistor which is heavily doped to produce large number of majority carriers is

• A. emitter
• B. base
• C. collector
• D. any of the above depending upon the nature of transistor

Answer 1

The Correct Option is A

To solve the question of which part of the transistor is heavily doped to produce a large number of majority carriers, let's break down the roles of the various parts of a transistor:

1. Emitter: The emitter is the part of the transistor that is heavily doped compared to other regions. This heavy doping increases the concentration of majority charge carriers (electrons in an NPN transistor and holes in a PNP transistor). The primary function of the emitter is to inject carriers into the base region.
2. Base: The base of the transistor is lightly doped and thin compared to the other regions. Its function is to pass the majority carriers from the emitter to the collector.
3. Collector: The collector is moderately doped. It collects carriers from the base, but it is not as heavily doped as the emitter. The collector is designed to handle the maximum amount of heat dissipated.

Based on the doping levels and their functions, the emitter is the correct answer, as it is heavily doped to produce a large number of majority carriers for efficient electron or hole injection into the base region.

Other options are incorrect because:

• Base: Lightly doped and its primary function is to facilitate carrier movement from emitter to collector.
• Collector: Moderately doped to collect carriers efficiently without being the primary source of carriers.
• Any of the above depending upon the nature of the transistor: This is inaccurate as doping levels are part of the transistor's architecture rather than variable aspects based on transistor nature.

Therefore, the correct answer is the emitter.