Thin Solid Films, Vol.363, No.1-2, 302-305, 2000
Contact resistance in interface of metal light emitting organic thin films
In this report, the specific contact resistance for the interface between the cathode metals and organic Alq(3) thin films were determined using the test pattern with a vertical structure between two contact pads. The samples with the structure of silver/Alq(3)/silver exhibited a linear current-voltage (I-V) characteristics and the specific contact resistance was calculated be in a range 1 x 10(-1) Omega/cm(2). The measurement of specific contact resistance for the samples with the structure of aluminum/Alq(3)/aluminum was hindered by the formation of the Al2O3 layer in the interface between aluminum and Alq3. The formation of oxide in the interface is believed to give rise to the Schottky characteristics and control the current transport across the cathode/organic interface. The barrier heights of the aluminum/Alq(3) contact were calculated to be in a range 0.22 to 0.60 eV, which is lower than the barrier height from the nominally pure aluminum/Alq(3) interface.
Keywords:DIODES