Patent ID: 7785958
Filing Date: 2010-08-31
Classification: H01L

Abstract:
1. A method for making a semiconductor device comprising: forming a first dielectric layer on a substrate; forming a trench within the first dielectric layer; forming a high-k gate dielectric layer on the substrate, the high-k gate dielectric layer having a first part that is formed at the bottom of the trench and a second part; forming a first metal layer on both the first and second parts of the high-k gate dielectric layer, the first metal layer being between about 25 and about 300 angstroms thick and having a first workfunction; depositing a donor metal layer, which comprises a workfunction shifting component, on a first part of the first metal layer; applying a high temperature anneal treatment to the donor metal layer to cause the workfunction shifting component to diffuse from the donor metal layer into the first metal layer to convert the first part of the first metal layer into a second metal layer with a second workfunction; applying the high temperature anneal treatment; and wherein: