Methods for forming a semiconductor gate electrode with a reflowed Co layer and the resulting device are disclosed. Embodiments include forming a trench in an ILD on a substrate; forming a high-k dielectric layer, a WF layer, and a Co layer sequentially on sidewall and bottom surfaces of the trench; reflowing a portion of the Co layer from the WF layer on the sidewall surfaces of the trench to the WF layer on the bottom surface of the trench; removing a remainder of the Co layer from the WF layer on the sidewall surfaces of the trench, above an upper surface of the reflowed Co; recessing the WF layer to the upper surface of the reflowed Co layer, forming a cavity above the reflowed Co layer; and filling the cavity with metal to form a gate electrode.