Metallic-compound films are formed by plasma-enhanced atomic layer deposition (PEALD). According to preferred methods, film or thin film composition is controlled by selecting plasma parameters to tune the oxidation state of a metal (or plurality of metals) in the film. In some embodiments, plasma parameters are selected to achieve metal-rich metallic-compound films. The metallic-compound films can be components of gate stacks, such as gate electrodes. Plasma parameters can be selected to achieve a gate stack with a predetermined work function.