Organic passivation layers for pentacene organic thin-film transistors

We studied the passivation layers for pentacene organic thin-film transistors (OTFTs) that were used to drive the active-matrix organic-light-emitting-diodes (AMOLEDs) fabricated by inkjet process. Conventional polyvinyl acetate (PVA) passivation layer could not protect OTFT channel from poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) inkjet process so that the performance was degraded critically after the process. By applying PVA/PVA/photoacryl (PA) multi-passivation layers, we could get OTFT arrays with switching ratio over 10⁶ even after PEDOT:PSS process. Using these OTFTs, we could drive AMOLEDs made by inkjet process.