FINFET WITH INSULATOR UNDER CHANNEL

摘要

A FinFET has a structure including a semiconductor substrate, semiconductor fins and a gate spanning the fins. The fins each have a bottom region coupled to the substrate and a top active region. Between the bottom and top fin regions is a middle stack situated between a vertically elongated source and a vertically elongated drain. The stack includes a top channel region and a dielectric region immediately below the channel region, providing electrical isolation of the channel. The partial isolation structure can be used with both gate first and gate last fabrication processes.

主权项

1. A method, comprising:
providing a semiconductor structure, the structure comprising:
a bulk semiconductor substrate; andat least one semiconductor fin, each fin comprising a top active region, a bottom region coupled to the substrate, and a dielectric region directly below the top region and above the bottom region, wherein a dielectric of the dielectric region encases the bottom region and the dielectric region; building a gate spanning the at least one fin over a channel region thereof; recessing areas of the top active region and the dielectric region on either side of the channel region after building the gate, such that the dielectric region remains only under the channel region; and creating a source and a drain in the recessed areas.