High resolution XPS studies on hexadecafluoro-copper-phthalocyanine deposited onto Si(111)7 x 7 surface

High resolution X-ray photoelectron spectroscopy measurements have been per formed onto ultrathin films of hexadecafluoro copper phthalocyanine deposit ed, at room temperature and in ultrahigh vacuum conditions, onto clean Si(1 1 1)7 x 7 substrate (silicon. Si). The measurements, performed at various film thicknesses, show a strong interaction between the molecule and the Si substrate. All the core level peaks present strong modifications induced b y the substrate interaction. In particular the fluorine (F) spectrum clearl y presents the effect of the interaction of some F atoms of the molecule wi th the substrate, which determines the formation of F-Si bonds while the co pper spectrum indicates a charge transfer from the Si substrate. The change s observed in the other core level spectra have been attributed to a differ ent charge distribution in the molecule. after the formation of F-Si bonds. We suggest a planar growth of these molecules on the Si substrate starting from the first layer. (C) 2001 Elsevier Science B.V. All rights reserved.