Simultaneous enhancement of charge transport and exciton diffusion in single-crystal-like organic semiconductors

The charge transport and exciton diffusion have been simultaneously enhanced in the highly ordered and oriented zinc phthalocyanine (ZnPc) films which are fabricated by weak epitaxy growth method compared to the normal ZnPc films (charge mobility from 4 x 10(-5) cm(2)/Vs to 1.1 x 10(-4) cm(2)/Vs and exciton diffusion length from 9 nm to 16 nm). The temperature dependent current-voltage (I-V) characteristics are utilized to investigate the charge transport mechanism, which reveal the clear mechanism and the role of traps in different films. These results reveal the direct relationship between traps properties and transport behavior of both exciton and charge. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692106]