J. Staudigel et al., Comparison of mobility and hole current activation energy in the space charge trap-limited regime in a starburst amine, APPL PHYS L, 75(2), 1999, pp. 217-219
Using two complementary methods, we have investigated the individual contri
bution of the space charge-limited hole transport in vapor-deposited films
of 4,4('),4(')-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (m-MTDA
TA) to the temperature behavior of organic light-emitting diodes. In single
-layer indium tin oxide/m-MTDATA/Ag structures, we have measured the activa
tion energies of the current density and of the hole mobility as a function
of the applied electric field. Both activation energies obtained under ste
ady-state and pulsed conditions are comparable, which confirms that the tem
perature behavior of the current density is predominantly governed by the h
ole mobility. (C) 1999 American Institute of Physics. [S0003-6951(99)00328-
9].