A series of magnetron-sputtered [Co(1 nm)/Au(tAu)]30 multilayers (MLs) has been deposited on Si(100) substrates covered with a 100 nm thick SiNx buffer layer. The samples were examined with x-ray diffraction (XRD), magnetotransport (MR), isothermal magnetization (M-H), and transmission electron microscopy (TEM) measurements. The quality of the interface and layer stacking in these MLs was observed with cross-section TEM and examined with superlattice refinement of the XRD patterns, where an (111) preferred orientation is evident along the growth direction. Three MR maxima, with values ΔR/Rs = 3.5%, 1.3%, and 1.1% were observed for Au layer thicknesses (tAu) of 2.5, 3.9, and 5.1 nm, respectively, in a range of applied magnetic fields less than ±100 Oe, that are attributed to the giant magnetoresistance (GMR) effect. In the [Co(1 nm)/Au(2.4 nm)]30 sample, the GMR coercivity is two orders of magnitude less than that observed in epitaxial structures. This makes the sputtered Co/Au MLs possible candidates for use in GMR applications. Below tAu = 2 nm a maximum anisotropic MR effect of 2% is observed for tAu = 0.6 nm. © 1998 American Institute of Physics.