Fully depleted silicon-on-insulator (fdsoi) transistor device and self-aligned active area in fdsoi bulk exposed regions

Abstract

Methods for eliminating the distance between a BULEX and SOI and the resulting devices are disclosed. Embodiments include providing a silicon layer on a BOX layer on a silicon substrate; forming two active areas in the silicon layer, separated by a space; forming first and second polysilicon gates over one active area, a third polysilicon gate over the space, and fourth and fifth polysilicon gates over the other active area, the second and fourth gates abutting edges of the space; forming spacers at opposite sides of each gate; removing the second, third, and fourth gates and the corresponding spacers; removing the silicon layer and BOX layer in the space, forming a trench and exposing the silicon substrate; forming second spacers on sidewalls of the trench; forming raised source/drain regions on each active area; and forming a p-well contact on the silicon substrate between the second spacers.