Researchers at Infineon Technologies have analysed various organic materials and developed a broad portfolio of processes that could be used in the future to manufacture high-quality silicon-based memories as well as organic transistors and circuits. Usage of conventional deposition processes and photo-lithographic patterning techniques will allow manufacturing of these devices in a cost effective manner. Infineon’s researchers presented several papers on these fundamental technologies at the 2003 IEEE International Electron Devices Meeting (IEDM) in Washington DC. The encouraging results shown in the performance, reliability, and temperature behaviour of transistors, circuits, and memories based on organic materials mark important milestones on the path to using organic materials for future electronic devices.
With regards to integration density and clock frequency, electronic devices using organic materials may not be a direct alternative to silicon-based integration, but offer the potential of extremely low-cost manufacturing and a high degree of flexibility. While the production of integrated circuits using silicon or other crystalline semiconductors requires weeks and a large number of sequential processes with expensive equipment, organic electronics can be manufactured at substantially lower cost. The potential uses of organic electronics are correspondingly low performance and cost-sensitive applications.
Infineon demonstrated several organic components performing at levels previously unattainable. Thin-Film Transistors (TFTs) build by the researchers use organic semiconducting molecules as the active layer and provide charge carrier mobilities in excess of 1 cm2/ Vs. Like silicon-based components, these organic transistors consist of several layers: substrate, gate electrode, gate insulator, source and drain contacts, organic semiconductors (e.g. pentacene or substituted oligothiophenes), and a protective passivation layer. Infineon reported at IEDM about developments of both hybrid organic/inorganic structures as well as pure organic chips. “The latest research results at Infineon show that organic-based ICs have potential applications in high volume and cost-critical applications where silicon-based chips may be unsuitable,” said Dr. Christoph Kutter, Senior Vice President of the Corporate Research Department at Infineon. “The advances on performance and reliability demonstrated at the 2003 IEDM encourage us to continue our investigations of organic material for usage in new electronic devices.”