Method for making a semiconductor device having a high-k gate dielectric

摘要

A method for making a semiconductor device is described. That method comprises forming on a substrate a high-k gate dielectric layer that includes impurities, then forming a silicon containing sacrificial layer on the high-k gate dielectric layer. After the silicon containing sacrificial layer has gettered the impurities from the high-k gate dielectric layer, the silicon containing sacrificial layer is removed, and a gate electrode is formed on the high-k gate dielectric layer. The method optionally includes exposing the high-k gate dielectric layer to a silicic acid containing solution until a silicon dioxide capping layer forms on the high-k gate dielectric layer, prior to forming a gate electrode on the capping layer.