A method of forming a semiconductor device, the method comprising providing a semiconductor layer, and providing a first layer of a first metal on the semiconductor layer. A second layer may be provided on the first layer of the first metal. The second layer may include a layer of silicon and a layer of a second metal, and the first and second metals may be different. The first metal may be titanium and the second metal may be nickel. Related devices, structures, and other methods are also discussed.