Applied Surface Science 336 (2015) 133–137 Contents lists available at ScienceDirect Applied Surface Science jou rn al h om ep age: www.elsevier.com/locate/apsusc Laser-induced forward transfer of a bis-pyrene compound for OTFTs Catalin Constantinescu a,∗ , Abdou Karim Diallo b , Anthony D’Aleo b , Frédéric Fages b , Christine Videlot-Ackermann b , Philippe Delaporte a , Anne-Patricia Alloncle a a Aix-Marseille Université, CNRS, LP3 (UMR 7341), 13288 Marseille Cedex 9, France b Aix-Marseille Université, CNRS, CINaM (UMR 7325), 13288 Marseille Cedex 9, France a r t i c l e i n f o Article history: Received 5 June 2014 Received in revised form 8 October 2014 Accepted 9 October 2014 Available online 17 October 2014 Keywords: Laser processing LIFT Organic semiconductor Thin film OTFT a b s t r a c t We present results on a newly synthesized bis-pyrene compound that, besides the typical fluorescence, also exhibits semiconducting properties. Thin films have been grown by vacuum thermal evaporation on oxidized silicon and on transparent quartz substrates. Micrometric-sized pixels have subsequently been printed by laser-induced forward transfer (LIFT), in air and at low pressure (90 mbar), by using a Nd:YAG laser source (355 nm, 50 ps pulse duration) to produce functional organic thin film transistors (o-TFTs). Top-contact (TC) configurations are emphasized, and the influence of the pressure and laser fluence during the LIFT procedure is discussed. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Pyrene is a polycyclic aromatic hydrocarbon made of four ben- zene rings that are peri-fused. Although most of pyrene compounds are used in the chemistry of dyes and dye precursors [1–3], its derivatives are also valuable molecular probes via fluorescence spectroscopy [3–5]. Having high quantum yield and lifetime, such compounds have been used to determine specific environments, e.g. photodegradation effects related to laser processing. Pyrene and its derivatives also exhibit significant – interactions, similar to acenes, thus making it a candidate in organic electronics [3,6–9]. Significant advances have been made in the realization of organic thin film transistors (OTFTs) starting from various acene or their derivatives, but also using pyrene-based compounds. The price of organic compounds that are used in most thin film devices is low, and will be even lower in the future. However, for an end product in electronics, fabrication and performance are dominant. The final test of organic transistor technology lies less in the reliability and performance of the organic components, which in some cases approach or even exceed the requirements of a particular application, but rather in the ability to manufacture ∗ Corresponding author. Tel.: +33 491829292; +33 491829512; fax: +33 491829289. E-mail addresses: constantinescu@lp3.univ-mrs.fr (C. Constantinescu), videlot@cinam.univ-mrs.fr (C. Videlot-Ackermann), alloncle@lp3.univ-mrs.fr (A.-P. Alloncle). such products at very low-cost. Hence, the efficient use of organic electronic materials will depend on capturing their low-cost poten- tial through the innovative fabrication of devices on inexpensive, large-area substrates and by using new, cost-efficient techniques, compatible with their physical and chemical properties. Herein, we present results on a pyrene-based compound for OTFT applications, namely 1,4-bis(octyloxy)-2,5-bis(ethynylpyrene)- benzene [9], further referred to as bis-pyrene. Bottom-gate top- contact (BGTC) configuration has been used for the OTFT devices based on bis-pyrene thin films grown on highly n-doped silicon wafers (the gate) covered with thermally grown silicon oxide (the dielectric/gate insulator). Furthermore, laser printed micrometric pixels of the bis-pyrene compound have also been tested as OTFTs. 2. Experimental 2.1. Materials and synthesis The bis-pyrene compound has been synthesized by react- ing 1,4-diiodo-2,5-bis(octyloxy)benzene with 2.2 equivalent of 1-ethynylpyrene [9–11] following the standard Sonogashira cross coupling conditions [12] yielding the symmetrical 1,4- bis(octyloxy)-2,5-bis(ethynylpyrene)benzene compound. This com- pound is expected to be planar, and therefore allowing it to stack in a suitable, efficient way. Details on the synthesis and purification methods are described elsewhere [9]. http://dx.doi.org/10.1016/j.apsusc.2014.10.037 0169-4332/© 2014 Elsevier B.V. All rights reserved.