Abstract

Organic thin-film transistors (OTFTs) were fabricated using various buffer layers between the active layer and source/drain electrodes. The device structure was glass/indium–tin oxide (ITO)/poly(methyl methacrylate) (PMMA)/pentacene/buffer layer/Ag (source/drain). N,N '-diphenyl-N,N '-bis(1-naphthyl-phenyl)-(1,1'-biphenyl)-4,4'-diamine (NPB), tris(8-hydroxyquinolino)-aluminum (Alq3), Alq3/NPB, and NPB/Alq3 films were used as the buffer layers, respectively. The OTFTs using stacked NPB/Alq3 as a buffer layer exhibited a field-effect mobility of 0.31 cm2 V-1 s-1, on–off drain current ratio of 6.7×105, and threshold voltage of -16.8 V. Additionally, the interface mechanism and contact resistance were determined by ultraviolet photoelectron spectroscopy (UPS) and the transmission line method (TLM). Experimental results indicate that a low energy barrier between the electrode and pentacene enhances the ability of holes to transfer from an electrode to pentacene. Moreover, inserting a buffer layer between the electrode and pentacene reduces the contact resistance. Such an improvement is attributed to the weak interface dipole at the interface of the active layer and electrodes.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.