Techniques Providing Metal Gate Devices With Multiple Barrier Layers

摘要

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.

主权项

1. A method comprising:
providing a semiconductor substrate; depositing a high-k (HK) dielectric layer over the semiconductor substrate; forming a dummy gate layer over the HK dielectric layer; removing the dummy gate layer over the HK dielectric layer; depositing a first metal compound barrier layer over the HK dielectric layer; depositing a second metal compound barrier layer over the first metal compound barrier layer, wherein the first and second metal compound barrier layers are formed by respective deposition processes; and depositing a stack of metal gate layers over the first and second metal compound barrier layers.