Spray deposition of organic semiconducting thin-films: Towards the fabrication of arbitrary shaped organic electronic devices

In order to fully exploit the potential of polymer electronics, large-area/low-cost processing technologies suitable for thin-film deposition on arbitrary substrate materials and geometries are necessary. One very promising, yet little examined, deposition technique compatible to large-area industrial-scale processes is provided by spray technology. In this article we present a detailed investigation on the layer formation process during spray deposition of organic thin-films and its relation to solution properties and process parameters. It is demonstrated that the layer formation process can be thought of as a process of successively stacking individual droplets. Microscopy investigations indicate that individual droplets in a spray-coated layer can behave to a certain extent as a continuous layer. The technological framework developed here is successfully applied to the fabrication of organic photo-detecting devices as well as organic thin-film transistors. Gaining insight into the layer formation process represents an important step towards the realization of arbitrary shaped organic electronic devices fabricated by spray deposition. (C) 2010 Elsevier B.V. All rights reserved.