Semiconductor device with metal gates and method for fabricating the same

摘要

A semiconductor device includes a gate insulation layer formed over a substrate and having a high dielectric constant, a gate electrode formed over the gate insulation layer and a work function control layer formed between the substrate and the gate insulation layer and inducing a work function shift of the gate electrode.

主权项

1. A method for fabricating a semiconductor device, comprising:
forming a first work function control layer over a first region of a substrate; forming a second work function control layer over a second region of the substrate; forming a gate insulation layer having a high dielectric constant over the first and second work function control layers; forming a gate conductive layer over the gate insulation layer; and forming a first gate and a second gate having different work functions in the first region and the second region, respectively, by etching the gate conductive layer, the gate insulation layer, the first work function control layer, and the second work function control layer, wherein the first work function control layer includes an aluminum oxide layer and a lanthanum oxide layer.