Methods for cutting (e.g., dividing) metal gate structures in semiconductor device structures are provided. A dual layer structure can form sub-metal gate structures in a replacement gate manufacturing processes, in some examples. In an example, a semiconductor device includes a plurality of metal gate structures disposed in an interlayer dielectric (ILD) layer disposed on a substrate, an isolation structure disposed between the metal gate structures, wherein the ILD layer circumscribes a perimeter of the isolation structure, and a dielectric structure disposed between the ILD layer and the isolation structure.