Figure shows the results of the XRD crystallographic analysis of metal films. The HEA film exhibited a single-phase FCC-type structure, which is distinct from the individual metal XRD patterns obtained at the same conditions. The lattice constants were calculated from the diffraction peaks of the (111) plane, which is the central peak of the fcc structure, and the results are shown in Table . The values of the crystal lattice constants showed excellent agreement with the average values of the five metals, and the crystal lattice structure was close to the values of palladium and platinum. This indicates that the elements were well mixed and formed a single-phase alloy.