Dimerization of titanyl phthalocyanine in thin films prepared by surface polymerization by ion-assisted deposition

Surface polymerization by ion-assisted deposition (SPIAD), the simultaneous dosing of hyperthermal ions while depositing an organic oligomer, was used to deposit titanyl phthalocyanine (TiOPc) thin films with 50 and 100 eV acetylene ions. The properties of the SPIAD TiOPc thin films are compared with films of the evaporated TiOPc monomer via examination of the electronic structure, ultraviolet-visible absorbance, and composition. Mass spectrometry, x-ray photoelectron spectroscopy, and other methods were used to determine the film composition, chemical bonding, and to examine the electronic structure. These results showed the formation of TiOPc dimers bound face to face. However, the overall phthalocyanine ring structure otherwise remained intact, except for small amounts of atmospheric oxidation at ion-induced radical sites. (C) 2008 American Vacuum Society.