Published online by Cambridge University Press: 25 February 2011
In the present study epitaxial Ni(001) films have been grown on natural C(001) substrates (type la and Ha) and homoepitaxial C(001) films. Two deposition techniques including electron-beam evaporation of Ni in a molecular beam epitaxy (MBE) system and evaporation of Ni from a resistively heated tungsten filament have been employed. As evidenced by scanning electron microscopy (SEM), the Ni films deposited by electron-beam evaporation were found to replicate the very fine, unidirectional scratches present on the as polished C(001) substrates. Indeed, the coverage and uniformity of the deposited films would imply a two-dimensional (2-D) growth mode. In comparison, the thermal evaporation of Ni on C(001) substrates results in a highly textured and faceted surface morphology indicative of three-dimensional (3–D) nucleation and growth. Moreover, Rutherford backscattering/channeling measurements have demonstrated that the Ni(001) films deposited by electron-beam evaporation are of superior crystalline quality. Differences in the observed microstructure and apparent growth modes of the epitaxial Ni(001) films have been attributed to the presence of oxygen incorporation in those layers deposited by thermal evaporation.