摘要 |
The invention relates to an ion-implantation process for fabricating integrated bipolar planar transistors, particularly transistors for very high frequencies. To prevent the variations in the thicknesss of the insulating layer, through which the dopants for the base region are implanted into the semiconductor body in the form of ions, from causing variations in current gain, the dopants for the emitter regions are implanted through the same insulating layer as the dopants for the base region. The total charge in the base region below the emitter region thus becomes substantially independent of thickness variations of the insulating layer through which the dopants for the emitter region and those for the base region are implanted.
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