Observation of hole injection boost via two parallel paths in Pentacene thin-film transistors by employing Pentacene: 4, 4"-tris(3-methylphenylphenylamino) triphenylamine: MoO₃ buffer layer

Pentacene organic thin-film transistors (OTFTs) were prepared by introducing 4, 4"-tris(3-methylphenylphenylamino) triphenylamine (m-MTDATA): MoO₃, Pentacene: MoO₃, and Pentacene: m-MTDATA: MoO₃ as buffer layers. These OTFTs all showed significant performance improvement comparing to the reference device. Significantly, we observe that the device employing Pentacene: m-MTDATA: MoO₃ buffer layer can both take advantage of charge transfer complexes formed in the m-MTDATA: MoO₃ device and suitable energy level alignment existed in the Pentacene: MoO₃ device. These two parallel paths led to a high mobility, low threshold voltage, and contact resistance of 0.72 cm(2)/Vs, -13.4 V, and 0.83 k Omega at V-ds = -100 V. This work enriches the understanding of MoO₃ doped organic materials for applications in OTFTs. (C) 2014 Author(s)