Alternate heteroepitaxial growth of chloroindium phthalocyanine and chloroaluminum phthalocyanine ultrathin multilayered structure and its xerographic and optical properties

(ClInPc/ClAlPcCl)(n) ultrathin multilayered structures and co-deposited ClI nPc-ClAlPcCl composite films were prepared by a high-vacuum organic-beam de position technique. The Q-band absorption is shifted with changes in the pe riod number and layer thickness. With a decrease in the period number, the energy splitting of the Q-band increased up to the maximum value and then d ecreased. The changes in optical absorption spectra of the ultrathin multil ayered structures are most likely to be due to the dipole-dipole and charge transfer interaction among the different molecular assemblies. The photose nsitivity of the ultrathin multilayered structures is over 10-fold better t han that of the co-deposited composite film. The improvement in xerographic properties is probably due to the fact that an ultrafast photo-induced cha rge transfer and separation can be generated from the interfacial potential barrier of (ClInPc/ClAlPcCl)(n) structures and the photogenerated holes ca n be swept out due to tunneling prior to recombination. The performance of these ultrathin multilayered structures makes them an efficient building bl ock for organic photoelectronic devices. (C) 2001 Elsevier Science B.V. All rights reserved.