'All-plastic' logic devices operate at world record speeds

This is the highest frequency reported to date for a unipolar ring oscillator fabricated using a solution processed organic semiconductor and gate dielectric. It is also expected that with trivial optimisation of the circuit design, oscillator frequencies well above 1MHz can be easily attained. 

ICs based on OTFTs have been in development for over 15 years with development scientists working on both the speed and complexity of integrated circuits for a range of electronics applications. However, one of the main barriers to the growth of printed electronic circuits was the ability to manufacture circuits using high-throughput, solution-coating techniques with the necessary semiconductor performance to allow fast logic circuits to be realised in standard digital circuits such as ring oscillators.

This result demonstrates that the historic barrier to realising fast, solution printed electronics no longer exists, opening the door to a wide range of exciting application possibilities. For instance, with the emergence of the IoT, one market requirement that has not been met is for low cost, thin, flexible and disposable RFID and NFC tags for the transmission of data from devices, sensors or objects. To achieve the necessary 53kb/s for an RFID or NFC device operating at the standardised frequency of 13.6MHz, a stage gate delay in the logic of less than 400ns is needed. SmartKems ring oscillator operates well below this requirement at 200ns, making it a lead contender as a platform technology for fully printed, low cost, flexible electronics.

A more immediate and pressing application is as a TFT backplane platform for the manufacture of conformal LCD and flexible AMOLED displays. Narrow bezels can now be achieved by the use of ‘integrated gate drivers’ fabricated on the display backplane. Whilst it was once thought that this could only be achieved using inorganic materials such as LTPS, this new result shows that SmartKem’s tru-FLEX would allow the manufacture of integrated gate drivers that would not only drive 4K2K displays but also offer the unique capability of true physical flexibility.

Steve Kelly, CEO and Founder, SmartKem, commented: “These are exciting times. Anuaryrnologyssed organic semi enabled devices spead. This is a great result and a testament to SmartKem’s world beating end-to-end capability in material and transistor expertise. This emphasises the enabling nature of material innovation in driving forward the potential of flexible electronics, not just for applications to smart, flexible electronics for the IoT for instance, but also the unique position it holds in enabling the growth of the flexible display industry.”

SmartKem’s tru-FLEX platform is an innovative semiconductor technology that has gained significant traction globally as the TFT technology of choice for display manufacturers seeking the next phase of added value in the consumer experience – the conformal and truly flexible thin-film transistor platform that combines low cost, ultra-flexibility and extremely low power consumption.

A key strength of the solution coated tru-FLEX TFT platform is that is can be adopted straight into existing display TFT backplane production lines commonly used by manufacturers in Asia without the need for any new equipment. SmartKem’s tru-FLEX provides display manufacturers with a semiconductor ink that allows high throughput, low temperature solution coating using standard slit coat equipment on low cost plastic substrates. These ultra-flexible TFT arrays can then be integrated as a pixel driver ‘backplane’ array for the manufacture of conformal LCD and ultra-flexible AMOLED displays for wearable, mobile and large area applications.