What is the name of the three poles of a semiconductor triode?

Transistor is one of the basic components of semiconductor, which has the function of current amplification and is the core component of electronic circuit. Triode consists of two PN junctions, which are very close to each other on a semiconductor substrate. Two PN junctions divide the positive semiconductor into three parts, the middle part is the base region, and the two sides are the emitter region and the collector region. The arrangement is PNP and NPN.

The corresponding electrodes are led out from three areas, namely

Cardinal b

Emitter e

Collector C.

The PN junction between emitter and base is called emitter junction, and the PN junction between collector and base is called collector. The base region is thin, while the emitter region is thick and the impurity concentration is high. The emitter region of PNP triode "emits" holes, and its moving direction is consistent with the current direction, so the emitter arrow is inward; The emitter of NPN transistor "emits" free electrons, which move in the opposite direction to the current direction, so the emitter arrow is outward. The transmitter arrow points outward. The emitter arrow points to the conduction direction of PN junction under DC voltage. There are two kinds of silicon transistors and germanium transistors: PNP and NPN.