Photogenerated charge carriers in double-layer organic field-effect transistor

Photogenerated carriers in active double-layer 3,4,9,10-perylenetetracarboxylic dianhydride/copper phthalocyanine (PTCDA/CuPc) organic field-effect transistor (OFET) have been investigated. The PTCDA and CuPc layers haven-and p-type conductivities, respectively; thus, PTCDA can be assumed as an acceptor and CuPc as a donor in the meaning of photovoltaic device. It has been found that the charges are generated in the bulk of the organic material rather than close to the organic-organic interface. Hence, it is suggested that exciton dissociation takes a place on the oxygen- and hydrogen-related defects in the organic film and supported by the molecular simulation of defects' energy states. (C) 2013 Elsevier B.V. All rights reserved.