A semiconductor component includes: a semiconductor substrate (110); an
epitaxial semiconductor layer (120) above the semiconductor substrate; a
bipolar transistor (770, 870) in the epitaxial semiconductor layer; and
a field effect transistor (780, 880) in the epitaxial semiconductor layer.
A portion of the epitaxial semiconductor layer forms a base of the bipolar transistor
and a gate of the field effect transistor, and the portion of the epitaxial semiconductor
layer has a substantially uniform doping concentration. In the same or another
embodiment, a different portion of the epitaxial semiconductor layer forms an emitter
of the bipolar transistor and a channel of the field effect transistor, and the
different portion of the epitaxial semiconductor layer has a substantially uniform
doping concentration that can be the same as or different from the substantially
uniform doping concentration of the portion of the epitaxial semiconductor layer.
