Growth mode and self-organization of LuPc2 on Si(001)-2 x 1 vicinal surfaces: An optical investigation

S. Boudet (1, 2) , I. Bidermane (1, 2) , Emmanuelle Lacaze (1, 2) , B. Gallas (1) , M. Bouvet , J. Brunet , A. Pauly (3) , Yves Borensztein (1, 2) , N. Witkowski (1, 2)

1 INSP - Institut des Nanosciences de Paris
2 INSP-E6 - Physico-chimie et dynamique des surfaces
3 IP - Institut Pascal

We report an investigation of the initial growth and of the self-organization of lutetium biphthalocyanine LuPc2 on Si(001)-2 x 1 vicinal surfaces. Using surface-sensitive optical spectroscopies, namely, surface-difference-reflectance spectroscopy (SDRS) and reflectance-anisotropy spectroscopy (RAS), together with local-probe microscopies, we are able to propose a scenario for the growth mode up to about 20 nm. We demonstrate that the growth mode initially proceeds through the formation of a wetting layer, followed by the formation of clusters whose sizes increase while keeping a constant shape in which the molecules are inclined. Moreover, the LuPc2 molecules are self-organized along the step edges, and we are able to estimate that about 30% to 100% of the molecules are aligned when considering that the molecules are tilted by 45 degrees to 63 degrees with respect to the surface normal.

Domaines: Matière Condensée [cond-mat]

S. Boudet, I. Bidermane, Emmanuelle Lacaze, B. Gallas, M. Bouvet, et al.. Growth mode and self-organization of LuPc2 on Si(001)-2 x 1 vicinal surfaces: An optical investigation. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012, 86 (11), pp.115413. ⟨10.1103/PhysRevB.86.115413⟩. ⟨hal-01238974⟩