We develop a universal method for spray-deposition of polymeric semiconductor blends, based on blends of polyfluorenes (F8TBT), polythiophenes (P3HT) and fullerenes (PCBM), as suitable for large areas. A multi-faceted characterisation approach, studying photoluminescence quenching, together with atomic force and optical microscopy, illustrates favourable results in terms of layer thickness, uniformity, and mesoscale morphology. With key engineering tolerances in mind, thermal (melt) and solvent-vapour annealing are investigated as post-processing methods, for improving the planarity of craterform layers and blend photophysical characteristicsPeer reviewe