Printed organic circuits have the potential to revolutionize the spread of electronic applications. This will be enabled by inexpensive and fast fabrication with printing techniques using soluble organic materials. Two main challenges have to be mastered on the way towards printed electronics. First, the development of stable transistors and an adapted chip design for organic materials, and second, the development of a reliable fabrication process. We present our results on high performance polymer transistors, mainly based on poly-3alkylthiophene (P3AT) as semiconducting material. Fast circuits up to 200 kHz and stable circuits with operation lifetimes of more than 1000 h under ambient conditions without any encapsulation are shown. We also report on a fully printed, all organic ring oscillator.

Using soluble polymers for the active layer and insulating layer, we report on a concept for the fabrication of fast integrated circuits based on p-type organic transistors only. Ring oscillators with frequencies above 100 kHz and propagation stage delays below 0.7 μs are presented. They show a very stable performance over time even without encapsulation, when stored and measured under ambient conditions. Regioregular poly(3-alkylthiophen) is used as the active semiconducting layer, a polymer blend as the insulator, a flexible polyester film as the substrate and metal electrodes. To enable vertical interconnects, the insulating layer is patterned.

The discovery of (semi) conducting polymers opened a route to the fabrication of microelectronics by printing. We designed structural and electrical properties of printed polymeric thin films and multilayers to set up field-effect transistors. The polymeric transistors are fully logic capable as is proven by persistent operation of an integrated ring-oscillator circuit. Solution processing of the polymers in printing is completely done under ambient conditions resulting in stable operation of the printed transistors and microcircuits.

Detailed investigations on shelf life and operation lifetime of polymer field-effect transistors (PFETs) and circuits are reported. All examined devices consisted entirely of polymer materials except the electrodes. Regioregular poly(3-alkylthiophene) was used as a semiconductor. Unencapsulated devices were produced, stored, and measured under ambient conditions. The performance of PFETs was maintained for more than 12 months after production. Even under extreme conditions of 85 °C and 85% relative humidity, a stable shelf life of more than 1400 h was measured. Transistors exceeded a continuous operation time of 1000 h. Operation lifetimes showed that the degradation did not follow the Arrhenius lifetime-temperature relationship. Similar results were found for ring oscillators.

The roadmap for organic and printed electronics is a key activity of the OE-A, the industrial organisation for the young organic, printed and large area electronics industry. Organic electronics is a platform technology that enables multiple applications, which vary widely in their specifications. Since the technology is still in its early stage-and is in the transition from lab-scale and prototype activities to production-it is important to develop a common opinion about what kind of products, processes and materials will be available and when. This chapter is based on the third version of the OE-A Roadmap for organic and printed electronics, developed as a joint activity by key teams of experts in 9 applications and 3 technology areas, informed by further discussions with other OE-A members during association meetings. The resulting roadmap is a synthesis of these results representing common perspectives of the different OE-A forums. Through comparison of expected product needs in the application areas with the expected technology development paths, potential roadblocks or ''red brick walls'' such as resolution, registration and complementary circuitry are identified.