We investigate the properties of sputtered aluminum silicon oxynitride layers for application as transparent permeation barrier front sheets for flexible opto-electronic applications. We compare the results from mixed aluminum-silicon and pure silicon targets when the reactive gas content is varied in a dynamic roll-to-roll process on the optical, structural, permeation properties of the layers. We observe that permeation barrier layers deposited from mixed aluminum-silicon targets shows a change in layer growth and the resulting properties compared with layers from a pure silicon Target.