Forming symmetrical stress liners for strained CMOS vertical nanowire field-effect transistors

摘要

A method of forming symmetrical stress liners to maintain strain in CMOS vertical NW FETs and the resulting device are provided. Embodiments include providing a doped semiconductor layer on an upper surface of a substrate; providing a semiconductor nanowire on the doped semiconductor layer; forming a first stress layer on the doped semiconductor layer surrounding the semiconductor nanowire; forming a gate electrode layer on a portion of the first stress layer on opposite sides of the semiconductor nanowire; forming a gate dielectric layer on the first stress layer between the gate electrode layer and the semiconductor nanowire; forming an oxide layer on a remaining portion of the first stress layer; forming a second stress layer on the oxide layer, the gate dielectric layer and the gate electrode layer; and forming contacts to the gate electrode layer, the semiconductor nanowire, and the doped semiconductor layer.