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arXiv · 0808.1048

Charge carrier induced barrier height reduction at organic heterojunctions

S. W. Tsang·M. W. Denhoff·Y. Tao·Z. H. Lu
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Abstract

In order to provide an accurate theoretical description of current density voltage (J-V) characteristics of an organic heterojunction device over a wide range of electric fields at various temperatures, it is proposed that an accumulation of charge carriers at the heterojunction will lead to a reduction in the barrier height across the heterojunction. Two well-known hole transporting materials, 4,4,4-Tris(N-3-methylphenyl-N-phenyl-amino) triphenylamine (MTDATA) and N,N-diphenyl-N,N-bis(1-naphthyl)(1,1-biphenyl)-4,4diamine (NPB) were used to fabricate unipolar heterojunction devices. It is found that the J-V characteristics depends strongly on applied bias. The simulated J-V characteristics of the heterojunction device, with the modified injection model, are found to be in excellent agreement with the experimental data.

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S. W. Tsang, M. W. Denhoff, Y. Tao, Z. H. Lu. 2008-08-07. Charge carrier induced barrier height reduction at organic heterojunctions. https://doi.org/10.1103/physrevb.78.081301

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