23. September 2020, 13:22 Uhr | Kathrin Veigel
At the TU Dresden, novel organic components were developed, for example for foldable cell phones.
Scientists at TU Dresden have come a step closer to the vision of a broad application of flexible, printable electronics: They have now succeeded for the first time in developing powerful vertical organic transistors with a double control electrode.
Thanks to research by scientists at the Institute of Applied Physics at TU Dresden, high-resolution roll-up televisions or foldable smartphones may soon no longer be unaffordable luxury goods that can only be admired at international electronics trade fairs. A decisive prerequisite for the mechanically flexible electronic circuits required for this are high-performance organic transistors, on which the Organic Devices and Systems Group (ODS) at the Dresden Integrated Center for Applied Photophysics (IAPP) of the Institute of Applied Physics headed by Dr. Hans Kleemann is conducting research.
However, conventional horizontal organic thin-film transistors are very slow due to the bounce transport in organic semiconductors, so they cannot be used for applications requiring high frequencies. Especially for logic circuits with low power consumption, such as those used for Radio Frequency Identification (RFID), it is absolutely necessary to develop transistors with high switching frequencies and adjustable characteristics (threshold voltage). The team around Dr. Hans Kleemann has now succeeded in realizing such novel organic components.
»Until now, vertical transistors were rather exotic and were considered difficult to integrate into electrical circuits. Thanks to the vertical transistors with double control electrode developed by us, it is now possible for the first time to realize complex logic states with the help of just a few transistors while at the same time exploiting the advantages of vertical architecture, such as high switching frequencies,« explains Dr. Kleemann.
The vertical organic transistors with double control electrode are characterized by a high switching frequency (a few nanoseconds) and an adjustable threshold voltage. Thanks to these developments, even single transistors can be used to represent different logical states (AND, NOT, NAND). Furthermore, the adjustable threshold voltage ensures signal integrity (noise margin) and low power consumption.
With this, the research group has set a milestone with regard to the vision of flexible and printable electronics. In the future, these transistors could make it possible to realize even sophisticated electronic functions such as wireless communication (RFID) or high-resolution flexible displays completely with organic components, thus completely dispensing with silicon-based electronic components.