Method of selectively doping the intrinsic collector of a vertical bipolar transistor with epitaxial base

摘要

The collector of a vertical bipolar transistor is selectively doped by a first implantation of dopants before the epitaxy of the base, and is selectivly doped by a second implantation of dopants through the epitaxial base. Two implanted zones with different widths are obtained. The base of the vertical bipolar transistor is thinned and the collector resistance is optimized.