POWER BJT WITH BASE BALLAST RESISTOR

摘要

The present invention relates to a power bipolar junction transistor having a base ballast resistor in a base region, capable of varying a resistance value of the base ballast resistor in accordance to a distance from an output terminal to make a uniform potential difference between the base and an emitter. According to the present invention, the power bipolar junction transistor is formed by a plurality of unit bipolar transistor cells connected in parallel with each other, and each unit bipolar transistor cells has the base ballast resistor. The base ballast resistor is produced in the same layer as the base region using the same material and the same production process as the base region, and protrudes in a ′��prime; shape in a region between a collector region and the base region for a power bipolar junction transistor structure; and the resistance value of the base ballast resistor becomes high as the base ballast resistor is closer to an output side. Therefore, the present invention improves the current driving capability of the power transistor, and prevents thermal runaway which occurs when the emitter current concentrates on one location, enabling the emitter current to flow evenly by controlling the potential difference between the base and the emitter to be applied uniformly.