Study on the transfer induced by laser of organic conducting thin films

Abstract
The Laser-Induced Forward Transfer (LIFT) [J. Bohandy et al., J. Appl. Phys. 63 (4), (1988) 1158.] technique has been performed on thin layers of organic conducting material for applications in plastic micro-electronics. This simple, single step, direct printing technique enables to make surface micro patterning or localized deposition of material. This process is a promising alternative for manufacture of organic electronic components on flexible supports when usual techniques, such like ink jet printing, cannot be considered. For instance, when the organic material has no solubility properties or when complex architectures are needed. It can be applied to sensitive materials without altering their properties [D. B. Chrisey et al., Chem. Rev. 103, (2003) 553-576; J. M. Fernández-Pradas et al., Thin Solid Films, 453-454, (2004) 27-30]. This opens the way to alternative manufacturing processes for the Organic Field-Effect Transistor (OFET) technology. The ejected material is highly forward directed, with an angular divergence on the order of 3° while propagating over a distance of 2 mm. The high directivity of the ejection with picosecond pulses duration shows that complex micro-structures with a high spatial resolution can be performed using the no contact LIFT technique. The influence of the distance between the donor and acceptor substrates on process reliability is also discussed. Moreover no limitation is expected to miniaturization, which is a necessary requirement.