With varying thickness of the spacer near the second oscillatory GMR peak i
n Co/Cu system, a series of glass/Fe/[Co/Cu](20)/Co multilayers are prepare
d by magnetronsputtering technique. The MR values are relatively small. Hig
h angle X-ray diffraction shows that the copper crystallizes in fee structu
re with (111) texture and the cobalt crystallizes in hcp structure with (00
2) preferential orientation. There is a mixed amorphous CoCu layer at the i
nterface due to the diffusion between cobalt and copper, which may decrease
the MR value. The thickness, the mass density for each sub-layer and the s
urfacial and interfacial roughnesses are refined from the X-ray specular re
flectivity measurement.