A method of forming a semiconductor device includes providing a device having a gate stack including a metal gate layer. The device further includes a spacer layer disposed on a sidewall of the gate stack and a source/drain feature adjacent to the gate stack. The method further includes performing a first etch-back process to the metal gate layer to form an etched-back metal gate layer. In some embodiments, the method includes depositing a metal layer over the etched-back metal gate layer. In some cases, a semiconductor layer is formed over both the metal layer and the spacer layer to provide a T-shaped helmet layer over the gate stack and the spacer layer.