Adsorption and self-assembly of fullerenes on Si(111)3×3-Ag: C60 versus C70

•Peculiarities of C60 and C70 adsorption behavior on Si(111)3×3-Ag were elucidated.•Room-temperature sticking probability for C70 is higher than that for C60.•C60 are more mobile than C70 on both Si(111)3×3-Ag and fullerene monolayer.•Growth mode of C60 is layer-by-layer, while that of C70 is multi-layer one.•Planar C60/C70 heterostructures were grown using alternating C60 and C70 deposition.

Behavior of C60 and C70 fullerenes adsorbed onto Si(111)3×3-Ag is compared on the basis of STM observations. Such characteristics as sticking coefficient, migration rate, attachment/detachment rate from the molecular islands are considered. Room-temperature sticking coefficient for C70 is slightly greater than that for C60. Due to their non-spherical shape, C70 are less mobile than spherical C60. For both types of fullerenes, mobility of molecules on the fullerene layer is significantly retarded as compared to that on bare Si(111)3×3-Ag surface. Self-assembly of C60 obeys layer-by-layer growth mode, while C70 follows multi-layer mode, a sign of a greater Ehrlich-Schwoebel barrier. Alternating deposition of C60 and C70 paves the way to fabricate planar C60/C70 heterostructures with the most promising results being obtained with nanostructured islands grown on C60 monomolecular layer.

Graphical AbstractDownload high-res image (232KB)Download full-size image