The emitter region in the PNP junction transistor is more heavily doped then the base region so that

The emitter region in a PNP junction transistor is more heavily doped than the base region for several reasons:

1. Charge Carriers: The emitter is heavily doped so that it can supply a large number of majority charge carriers (in this case, holes for a PNP transistor) for current flow.

2. Injection Efficiency: A heavily doped emitter improves the injection efficiency of the transistor. This means that a larger number of charge carriers can be injected from the emitter into the base.

3. Amplification: The heavy doping of the emitter region ensures that the transistor can provide the necessary amplification. The base region is lightly doped to ensure that it can easily receive the charge carriers from the emitter.

4. Base Width Modulation: The heavy doping of the emitter also helps to reduce the effect of base width modulation or the Early effect, which can affect the stability of the transistor's operation.

5. Current Gain: The heavy doping of the emitter and light doping of the base results in a large current gain, which is a desirable property in many applications of transistors.

In summary, the heavy doping of the emitter region in a PNP transistor is crucial for its efficient operation, including providing a large number of charge carriers, improving injection efficiency, providing amplification, reducing base width modulation, and achieving a large current gain.