SELF-ALIGNED HETERO-JUNCTION BIPOLAR TRANSISTOR AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A self-aligned HBT(hetero-junction bipolar transistor) is provided to reduce base parasitic resistance and parasitic capacitance between a base and a collector by forming a thick base electrode without using a pad insulation layer. CONSTITUTION: A collector layer and a collector electrode(74) are formed in a silicon substrate(70). A base electrode(75,76) is formed on the collector layer, composed of a protrusion and a body. The protrusion has the first opening exposing the surface of the collector layer. The body has the second opening exposing the surface of the collector layer. A base epi layer(79) is selectively grown on the collector layer exposed to the inside of the first opening. A sidewall spacer(78) is formed on the sidewall of the second opening, covering the protrusion. An emitter electrode(80) is formed on the base epi layer, having an overhang type that covers the sidewall spacer. An insulation layer is connected to the sidewall spacer, interposed between the overhang of the emitter electrode and the base electrode.