US Patent 7466206 Amplifier circuit

Amplifier circuit for amplifying an input signal, having a vertically integrated cascode that has a collector semiconductor region of a collector, adjacent to the collector semiconductor region, a first base semiconductor region of a first base, a second base semiconductor region of a second base, an intermediate base semiconductor region adjoining both the first base semiconductor region and the second base semiconductor region, and an emitter semiconductor region of an emitter adjacent to the second base semiconductor region, wherein a signal input is connected to the second base, and the first base is electrically coupled both to a voltage source that is independent of the input signal and to the collector.