Influence of structural properties on environmental stability of pentacene thin film transistors

► Sensitivity of pentacene OTFTs to the moisture increases with increasing active layer growth rate. ► High density of grain boundaries in pentacene active layer enhances the water diffusion. ► Pentacene active layers with improved structure reduce the need of water barrier layers. ► Long term stability (related to the oxygen diffusion) is not influenced by the pentacene structure. ► Oxygen barrier layer is required in order to avoid aging effects in pentacene O-TFTs.