2016 · Q18
In a bipolar junction transistor
General KnowledgePhysics
- Aall the three regions (the emitter, the base and the collector) have equal concentrations of impurity
- Bthe emitter has the least concentration of impurity
- Cthe collector has the least concentration of impurity
- Dthe base has the least concentration of impurity
Explanation
In a bipolar junction transistor the emitter is the most heavily doped region, the collector moderately doped, and the base is both the thinnest and the most lightly doped region. This light doping of the base is essential so that most charge carriers injected from the emitter cross into the collector. Hence the base has the least impurity concentration.