Interface structure and surface morphology of (Co, Fe, Ni)/Cu/Si(100) thin films

We have examined bilayer Co/Cu, Fe/Cu, and Ni/Cu films deposited by molecular-beam epitaxy on hydrogen-terminated [100] silicon substrates. The magnetic metal/copper interface was examined by atomic resolution transmission electron microscopy and compared with the surface morphology as depicted by atomic force microscopy. The general orientation relationships across the magnetic metal/copper interfaces were found to be: [001]Co, Ni∥[001]Cu; (010)Co, Ni∥(010)Cu and [001]Fe∥[001]Cu; (110)Fe∥(200)Cu. The latter system is equivalent to the [11̄ 1]Fe∥[011]Cu and (110)Fe∥(100)Cu Pitsch relationship, as has been reported earlier. Furthermore, there was a general correlation between interfacial and surface roughness, indicating that the initial interface character is propagated throughout the film during growth.