Structural and magnetic fourfold symmetry of Co/Cu multilayers electrodeposited on Si(001) substrates

We have observed in-plane fourfold symmetry of the magnetization and magnetoresistance in Co/Cu multilayers electrodeposited on Si(001) substrates covered with a thin evaporated Cu seed layer. The fourfold symmetry correlates with the in-plane crystalline structure of the multilayers. High-angle x-ray diffraction shows that the Co/Cu multilayers have a strong (001) texture. Phi-scan x-ray diffraction reveals that the multilayers have fourfold symmetry in the plane with a 45 degrees rotation with respect to the Si substrates. We estimated an anisotropy field of 98 mT from vector magnetization curves, which is in fairly good agreement with the value obtained from Co/Cu multilayers electrodeposited on (001) Cu single crystal substrates. The giant magnetoresistance appears to depend on the in-plane orientation of the multilayer due to the magnetocrystalline anisotropy. (C) 1998 American Institute of Physics. [S0021-8979(98)00415-0].