Bipolar transistor structure having a reduced base resistance, and method for fabricating a base terminal zone for the bipolar transistor structure

摘要

To reduce the base resistance in a bipolar transistor structure as is used especially in large-scale-integrated (LSI) circuits, the base terminal zone is designed as a three-layer structure. The three-layer structure contains a first p-doped polysilicon layer (3), a metal silicide layer (4), a second p-doped polysilicon layer (5) and an insulating layer (6). The first polysilicon layer (3), the metal silicide layer (4) and the second polysilicon layer (5) have common vertical etching profiles. The surface and the flanks of the three-layer structure are covered with an oxide layer (6). IMAGE