Integration of organic LEDs and amorphous Si TFTs onto unbreakable metal foil substrates

Abstract
A long sought goal has been a flat panel display that is unbreakable, lightweight, flexible, and low-cost. Organic LEDs (OLEDs) have the potential for such a technology because of their demonstrated performance, their lack of a need for a crystalline substrate, and potential low cost (e.g, deposition by spin-coating). Amorphous Si (a-Si) TFTs are in widespread production for the switching and storage elements in active matrix liquid crystal displays (AMLCDs). Both of these technologies, however, are conventionally fabricated on breakable glass substrates. In this paper, we report the integration of amorphous Si TFTs and OLEDs onto thin stainless steel foils, and the demonstration of a simple circuit in which the TFT drives the OLED. The finished substrate (40/spl times/40 mm/sup 2/) has been dropped down 30 feet onto a concrete floor with no degradation in device performance. The work shows that a-Si TFTs can provide adequate current levels to drive OLEDs.