Researchers at the TU Dresden, Germany have implemented high-frequency essential building blocks with low power consumption using organic materials.
Semiconductor devices are reaching their limits of performance. Modern electronic systems need faster devices with low-power consumption and low production costs. Organic semiconductors have many properties including light weight, low-cost production, low-temperature processing, mechanical flexibility, and abundant availability. This makes them a better choice for fabricating electronic circuits.
Organic materials are key for printable and flexible electronics. But organic devices have a high rise and fall time which means that the speed is lower due to parasitic capacitances and other physical properties. The poor performance of these devices is impeding the commercialization of flexible and printable electronics.
Researchers at the Technical University of Dresden have successfully implemented a complementary vertical organic transistor technology, which is able to operate at low voltage, with adjustable inverter properties, and a fall and rise time demonstrated in inverter and ring-oscillator circuits of less than 10 nanoseconds, respectively.
Logic circuits like inverters are building blocks for mostly all digital circuits. Therefore, the development of high-frequency inverter and oscillator circuits with low power consumption and fast response time is an essential step for development of the flexible and printable electronics of the future.
Some months ago, a Ph.D. student at the TU Dresden, Erjuan Guo, announced the development of efficient, printable, and adjustable vertical organic transistors.
“In previous publications, we found that the second control-electrode in the vertical transistor architecture enables a wide-range of threshold voltage controllability, which makes such devices become ideal for efficient, fast and complex logic circuits. In the recent publication, we add a vital feature to the technology by demonstrating complementary circuits such as integrated complementary inverters and ring-oscillators. Using such complementary circuits, the power- efficiency and speed of operation can be improved by more than one order of magnitude and might possibly allow organic electronics to enter the GHz-regime,” explains Erjuan Guo, who received a Ph.D. from Technische Universität Dresden.
The work is described in the journal Nature Electronics.
About the researchers
The study was undertaken by the research group “Organic Devices and Systems” (ODS) at the Institute of Applied Physics (IAP) at TU Dresden headed by Dr. Hans Kleemann is working on the development of novel organic materials and devices for high performance, flexible and possibly even biocompatible electronics and optoelectronics. Increasing the performance of organic circuits is one of the key challenges in their research.