A semiconductor device with a metal gate is disclosed. An exemplary semiconductor device with a metal gate includes a semiconductor substrate, source and drain features on the semiconductor substrate, a gate stack over the semiconductor substrate and disposed between the source and drain features. The gate stack includes a HK dielectric layer formed over the semiconductor substrate, a plurality of barrier layers of a metal compound formed on top of the HK dielectric layer, wherein each of the barrier layers has a different chemical composition; and a stack of metals gate layers deposited over the plurality of barrier layers.