Spray-coating techniques have recently emerged as especially effective approaches for the deposition of small semiconducting molecules toward the fabrication of organic field-effect transistors (OFETs). Despite the promising mobility values and the industrial implementation capability of such techniques, the resulted devices still face challenges in terms of morphology control and performance variation. In this work, the efficient process control of electrostatic spraying deposition (ESD) and the excellent film properties of polymer:small molecule blends were successfully combined to develop reliable and high performance transistors. Specifically, a highly efficient blended system of 2,8-difluoro-5,11-bis(triethylsilylethynyl)-anthradithiophene (diF-TES-ADT) and poly(triarylamine) (PTAA) was employed in order to realize top-gate OFETs under ambient conditions, both on rigid and on flexible substrates. The films revealed an extensive crystallization and microstructural organization implying a distinct phase separation in the electrosprayed blend. Furthermore, we investigated the effects of the processing temperature on the film-forming properties by means of film continuity and grains boundaries.Remarkably, the electrosprayed OFETs exhibited field-effect mobilities as high as 1.71 cm 2 /Vs, and enhanced performance consistency when compared to conventional gas-sprayed transistors. Additionally, the transistors showed excellent electrical and environmental stability, indicative of the good interface quality and the selfencapsulation capability of top-gate structure. These results highlight the great potential of electrohydrodynamic atomization techniques for implementation to large-area processing for OFETs fabrication.

High performance organic transistors have been realized via airbrush technique, using small molecule-insulating polymer blends.

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