LATERAL BIPOLAR JUNCTION TRANSISTOR HAVING GRADED SiGe BASE

摘要

A lateral bipolar junction transistor is fabricated using a semiconductor-on-insulator substrate. The transistor includes a germanium gradient within a doped silicon base region, there being an increasing germanium content in the direction of the collector region of the transistor. The use of a substrate including parallel silicon fins to fabricate lateral bipolar junction transistors facilitates the inclusion of both CMOS FinFET devices and lateral bipolar junction transistors having graded silicon germanium base regions on the same chip.

主权项

1. A method comprising:
obtaining a structure comprising a plurality of parallel silicon fins adjoining an electrically insulating layer and a dummy gate extending across a plurality of the silicon fins, the fins defining a channel region having a first conductivity type beneath the dummy gate, a source region on a first side of the dummy gate, and a drain region on a second side of the dummy gate; diffusing germanium into the channel region of the structure to form a germanium gradient within the channel region having an increasing germanium content in the direction of the drain region; removing the drain region; epitaxially growing a silicon region on the second side of the dummy gate and from the fins within the channel region subsequent to forming the germanium gradient; doping the silicon region such that the silicon region has a second conductivity type opposite to the first conductivity type; replacing the dummy gate with a gate structure operatively associated with the channel region, and forming electrical connections to the gate structure and the silicon region.