| 摘要 |
A number of npn and pnp bipolar transistors are formed in a single chip of silicon, so that some of the transistors have a greater frequency response than others The higher frequency transistors have their emitters located closer to the collectors, by positioning a collector, or emitter, of a transistor in a recessed portion of the surface of the chip. The recess is formed in an accurate and controlled manner by locally oxidising the silicon surface, and subsequently removing the oxide to leave the recess.
|
