Abstract: The exchange bias field of NiFe/FeMn films with Ta/ Cu buffer was proved to be lowerthan that of the films with Ta buffer. The crystallographic texture, surface roughnessand elements distribution were examined in these two sets of samples, and there isno apparent difference for the texture and roughness. However, the segregation ofCu atoms above NiFe surface in the maltilayer of Ta/Cu/NiFe has been observed byusing the angle-resolved X-ray photoelectron spectroscopy (XPS). The decrease of theexchange bias field for NiFe/FeMn films with Ta/ Cu buffer layers is mainly causedby the Cu atoms segregation at the interface between NiFe and FeMn.

Key words: NiFe/FeMn, exchange bias field, texture, surface roughness, sur-face segregation