X-ray photoelectron spectroscopy studies on hexadecafluoro-copper-phthalocyanine ultrathin films deposited onto Si(100) 2 x 1

We have deposited in ultrahigh vacuum conditions very thin films of hexadecafluoro copper phthalocyanine onto both a clean, reconstructed Si(100) 2 x 1 substrate and a clean but unreconstructed Si(100) surface. We have studied the organic-inorganic interface by means of monochromatic X-ray photoemission spectroscopy. The measurements show an effective interaction between the molecule and the silicon substrate, in particular for a well-reconstructed silicon surface. The results suggests the important role of the negatively charged sites on the Si (100) 2 x 1 surfaces in the silicon-molecule interaction. (C) 1999 Elsevier Science B.V. All rights reserved.