Room Temperature Growth of Homogeneous Ultrathin Co Films on 6H-SiC (0001)-6 square root of 3 x 6 square root of 3R30 deg. Surface

The effect of a periodic template on the nucleation of cobalt clusters was studied by considering the nucleation phenomena of Co atoms on 6H-SiC (0001)- 6 square root of 3 x 6 square root of 3R30 deg. surface. The motivation of our study was to see whether the highly "porous" reconstruction allows the Co clusters to form regular-sized, periodic nano-islands. The nucleation process was studied by a combination of UHV-STM, RHEED, LEED and XPS. The 6H-SiC (0001)- 6 square toot of 3 x 6 square root of 3R30 deg. reconstructed surface, which contains homogenous honeycombs (2 approx. 3nm in diameter), can confine the Co atoms in the honeycomb and prevent its nucleation into larger clusters during the initial film formation stage at room temperature. The honeycomb layer also acts as a barrier against cobalt silicide formation. XPS results showed that no cobalt silicide was formed even after the sample was annealed to 1100 C. We propose that this can be a novel method to prepare ferromagnetic nano-metal arrays.