Growth behavior of CuPc films by physical vapor deposition

Various Cu-phthalocyanine (CuPc) films were grown from physical vapor deposition on top of indium-tin-oxide glass substrates by controlling substrate temperature (T-sub), source temperature (T-sou), and growth time. From side-view SEM pictures, the growth rates for these CuPc films are estimated and can be categorized into three regions. From the Arrhenius plot of growth rate versus 1/T-sub, the activation energy E A can be obtained. As T-sou = 390 degrees C, for region (A) with T-sub < 140 degrees C, the growth of CuPc films is dominated by the adhesion process with E-A = 810 meV. For region (B) with 140 degrees C < T-sub < 320 degrees C, the growth is then limited by the steric character associated with the organic molecular solids with E-A = 740 meV. For region ( C) with T-sub > 320 degrees C, the re-evaporation of the CuPc adhered molecules from the interface becomes dominant. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim