We have prepared iron-iron nitride multilayers by sequential reactive-nonreactive sputtering. The structure of the FeFe2N interfaces has been studied and found to be correlated with the magnetic properties of such samples. They are found to remain sharp enough for direct observation of multilayers either by transmission electron microscopy or by small angle X-ray scattering despite a significant shift of the Fe(Fe,N) interfaces towards the iron layers as a result of nitrogen diffusion.