Effect of non-zero Schottky barrier on the J-V characteristics of organic diodes

Current-voltage (J -Vcharacteristics of poly(3-hexylthiophene) (P3HT) are studied at different temperatures upto high voltages ∼ 20 V in the hole-only device configuration. The characteristics are studied in the temperature range 310-210K. In the intermediate voltage range the J -V characteristics follow J V ^l+1 , where l > 1 . As the voltage increases to high values J still varies as a power law i.e. as V^m, but contrary to the literature result m becomes < 2 . This behavior is explained theoretically in terms of non-zero injection Schottky barriers. The complete analytical expressions for the actual trap filled limit voltage (V′ _TFL) and J -V curves beyond V′ _TFL are presented.