US Patent 10516034 Semiconductor device and methods of manufacture

A semiconductor device and method of manufacturing are provided. In an embodiment a first nucleation layer is formed within an opening for a gate-last process. The first nucleation layer is treated in order to remove undesired oxygen by exposing the first nucleation layer to a precursor that reacts with the oxygen to form a gas. A second nucleation layer is then formed, and a remainder of the opening is filled with a bulk conductive material.