Stability improvement of organic TFTs by selective interface treatment for display applications

We have developed a flexible full-color OLED display driven by pentacene organic TFTs (OTFTs) with bottom-gate bottom-contact configuration. We will discuss an integration process of the display and improvement of stability by selective treatment of interfaces in the OTFTs. We have developed selective treatment of the surface of poly (vinyl-phenol) gate insulator using the selective growth of poly( p -chloroxylylene) after S/D electrode formation. This treatment has reduced deep carrier-trap density at semiconductor/gate insulator interface and has drastically suppressed bias-stress instability of the OTFTs. Direct carrier-injection structure with selective tiole treatment of S/D electrodes has been also developed. This suppresses the degradation of the OTFT due to increase of contact resistance in the integration. These techniques are promising for reliable display applications.