Research team brings 'rollable' displays closer to reality
A team of researchers from the University of Surrey has teamed up with scientists from Philips to create a technology that could see flexible electronics such as affordable roll-up tablet computers become widely available in the near future. They are continuing to develop the 'Source-Gated-Transistor' (SGT) that according to them is a simple circuit component invented jointly by the teams.
The researchers originally discovered that the component could be applied to many electronic designs of an analog nature, such as display screens but the new research work now shows that SGTs can also be applied to next-generation digital circuits.
Until now this area of electronic design has been hampered by unreliability and production complexity.
SGTs control the electric current as it enters a semiconductor, which decreases the odds of circuit malfunction, improves energy efficiency and keeps fabrication costs to a minimum. The properties make SGTs ideal for next-generation electronic devices, and could enable digital technologies to be incorporated into wearable designs built using flexible plastics or clothing textiles.
Such technologies may include ultra-lightweight and flexible gadgets which can be rolled up to save space when not in use, smart plasters, thinner than a human hair, that can wirelessly monitor the health of the wearer, low-cost electronic shopping tags for instant checkout, and disaster prediction sensors, used on buildings in regions that are at high risk of natural disasters.
These technologies involve thin plastic sheets of electronic circuits, similar to sheets of paper, but embedded with smart technologies. Until now, such technologies could only be produced reliably in small quantities, and that confined them to the research lab. However, with SGTs we have shown we can achieve characteristics needed to make these technologies viable, without increasing the complexity or cost of the design, said lead researcher Radu Sporea, Advanced Technology Institute (ATI), University of Surrey.
Professor Ravi Silva, director of the ATI and a co-author of the work, explained: This work is a classic example of academia working closely with industry for over two decades to perfect a concept that has wide-reaching applications across a variety of technologies. Whilst SGTs can be applied to mainstream materials such as silicon, used widely in the production of current consumer devices, it is the potential to apply them to new materials such graphene that makes this research so crucial.
By making these incredible devices less complex and implicitly very affordable, we could see the next generation of gadgets become mainstream much quicker than we thought, added Sporea.
The technology may also have applications in LED lighting because it could be used either in the control circuitry or in the actual light-emitting-element drivers although Sporea cautioned that these devices are comparatively low-current for the same geometrical footprint compared to conventional thin-film transistors and may not be able to handle the current to drive OLED/pixels, however, as light emitting materials improve, this may be offset.
An SGT device structure has been identified as an ideal choice for achieving energy-efficient AMOLED pixel circuits. The work of Sporea is funded by the Royal Academy of Engineering Academic Research Fellowship Programme.
- Paul Buckley
EE Times Europe