Solid-State Processing of Organic Semiconductors

Baklar, Mohammed A.; Koch, Felix; Kumar, Avinesh; Domingo, Ester Buchaca; Campoy-Quiles, Mariano; Feldman, Kirill; Yu, Liyang; Wobkenberg, Paul; Ball, James; Wilson, Rory M.; McCulloch, Iain; Kreouzis, Theo; Heeney, Martin; Anthopoulos, Thomas; Smith, Paul; Stingelin, Natalie

ADVANCED MATERIALS

2010

In summary, we advanced solid-state processing of a broad spectrum of organic semiconducting species as an efficient alternative to vacuum deposition, solution- or melt-processing technologies, and precursor routes. We demonstrated that bulk carrier mobilities derived from TOF studies did not deteriorate, but in some cases actually could be significantly enhanced when compared to conventionally processed structures. Advantageously, interfacial charge transport both for electrons and holes was not affected, despite processing the organic semiconductors in light and air. Clearly, there is ample room for improvement, notably in enhancing the physical interface between the active species and substrates—most importantly the gate dielectric and source/drain electrodes in case of FET structures—especially when bearing in mind that deformation of plastic crystals is critically influenced by temperature and the magnitude of pressure and rate at which it is applied. In addition, the initial particle size of the solid semiconductors may be adjusted, for instance, via dispersion or emulsion polymerization, to reduce the film thickness of solid-state pressed architectures.