Growth of Cu phthalocyanine thin films on Sb passivated vicinal Si(111) with molecular columns parallel to the surface

Abstract

This study shows a growth of copper phthalocyanine (CuPc) thin films with one-dimensional structures parallel to the surface on Sb-passivated stepped silicon surfaces with (111) orientation. Sb passivation maintains all the step and terrace features on the vicinal Si(111) surface, where subsequently a CuPc sub-monolayer is deposited. The CuPc forms islands of sub-micrometer extension, which shows substantial molecular diffusion on the surface after deposition. In a single island of CuPc, one-dimensional columns of stacked CuPc molecules grow parallel to the step edges of the vicinal Sb–Si(111) surface, which illustrates the strong anisotropy of molecular growth induced by the stepped surface. The self-assembly behavior of CuPc indicates that the Sb passivated surface allows high molecular mobility of CuPc, having anisotropy effect from the stepped substrate structure.