Spray-coating deposition for large area organic thin-film devices
A. Abdellah, D. Baierl, B. Fabel, P. Lugli, G. Scarpa
Technische Universitaet Muenchen, DE
Keywords: organic devices, deposition techniques, patterning
Abstract:Organic electronic devices based on solution-processable polymers are among the most promising applications of organic semiconductors. Low-cost fabrication by means of simple coating and printing techniques is surely one of their greatest advantages. We report the implementation and testing of an airbrush coating system for the fabrication of several organic electronic and optoelectronic devices using a commercially available airbrush unit. An analysis of different process parameters, e.g. operating pressure and sample distance, with respect to deposition characteristics and device performances was carried out and will be presented as well. In addition to fabricating devices with conventional stack design, our airbrush coating system allowed us to realize more complicated stacks consisting of several polymer layers deposited even from the same solvent. Such device architectures are rather complicated to realize using spin-coating due to partially dissolving previously deposited layers while applying the next. Multilayer device architectures were successfully implemented. Finally, a room-temperature nanoimprint lithography process has been used to directly pattern P3HT thin-film layers down to 20-nm feature sizes. This can be particularly appealing for increasing the efficiency of P3HT based bulk-heterojunction (BHJ) organic solar cells.