A conductive structure(s), such as a gate electrode(s) or a contact structure(s), and methods of fabrication thereof are provided. The conductive structure(s) includes a first conductive layer of a first conductive material, and a second conductive layer of a second conductive material. The second conductive layer is disposed over the first conductive layer, and at least a portion of the first conductive material includes grains having a size larger than a defined value, and at least a second portion of the second conductive material includes grains having a size less than the defined value. In one embodiment, the first and second conductive materials are the same conductive material, with different-sized grains.