Mechanism of Charge Injection in Metal/Copper-Phthalocyanine/Metal Structures

摘要

It is demonstrated that diode-like current-voltage(J-V) characteristics with very high rectification ratio can be achieved in indium tin oxide(ITO)/Copper-phthalocyanine(Cu-Pc)/metal single layer devices, if an electrode with low work function is used. But, an electrode with high work function, which is comparable to ionization potential of Cu-Pc, results no rectification. It has been shown that the J-V characteristics in the forward direction, when ITO is positively biased, can be explained by bulk limited space charge current modified with field dependent mobility. The J-V characteristics in the reverse direction, when ITO is negatively biased, can be described as tunneling due to Schottky-like barrier at metal/Cu-Pc interface.