Synthesis and elastic properties of V2AlC thin films by magnetron sputtering from elemental targets

The influence of deposition temperature on phase formation of V2AlC is studied by magnetron sputtering from elemental targets. At substrate temperatures below 750 0C, we observed the formation of AlxVy and V2C using x-ray diffraction (XRD) analysis. At 750 0C, a phase pure polycrystalline V2AlC film on a ∼12 nm thick transition layer has been observed using XRD and transmission electron microscopy. Selected area electron diffraction indicates that the film grown on the transition layer consists of phase pure V2AlC. As the substrate temperature is increased to 850 0C, the formation of V2C in addition to the V2AlC phase is observed. This may be due to desorption of aluminium causing the decomposition of V2AlC into vanadium carbides and aluminium. The V2AlC film is fully dense and polycrystalline and the elastic modulus based on nanoindentation is within the expected error margin consistent with previously reported theoretical calculations and the diamond anvil cell measurement of bulk V2AlC samples.