Comparison of p-channel transistors based on α,ω-hexyl-distyryl-bithiophene prepared using various film deposition methods

• Published in: Thin solid films 2010-07, Vol.518 (18), p.5311-5320
• Main Authors: Didane, Y., Martini, C., Barret, M., Sanaur, S., Collot, P., Ackermann, J., Fages, F., Suzuki, A., Yoshimoto, N., Brisset, H., Videlot-Ackermann, C.
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Electronics; Engineering Sciences; Exact sciences and technology; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Micro and nanotechnologies; Microelectronics; Morphology; Optical microscopy; Organic semiconductor; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film; Thin film structure and morphology; Transistors; Transport; X-ray diffraction
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.03.079

We present a series of organic thin film transistor (OTFT) devices realized by vacuum evaporation, spin-coating, drop casting and inkjet printing and a comparative analysis of their electrical response/behavior obtained under identical measurement conditions. A small molecule, α,ω-hexyl-distyryl-bithiophene DH- DS2T, was used as a hole transporting active layer. Structure and morphology of thin films have been studied by atomic force microscopy, X-ray diffraction and optical microscopy. Different parameters linked directly to the processes (solvent, concentration, deposition method, surface, post-treatment…) are identified as key factors controlling film quality/crystallinity and device performances. This systematic study reveals the factors that limit efficient charge transport at the macroscopic scale of the channel length in OTFT devices.