Scientist, working at Switzerland’s École Polytechnique Fédérale de Lausanne(EPFL), have laid the groundwork for advanced, reconfigurable and self-repairing electronic circuits. Capable of reorganizing its internal pathways under the application of external stimuli, these circuits represent the future of adaptable electronics. The technology could likely give birth to multi-tasking microchips that can switch functions by altering their pathways as well as repair damaged circuits.
Recently published in the Nature Nanotechnology journal, the research outlines the procedure by which ‘ferroelectric’ materials can be easily manipulated to develop flexible pathways that are several atoms wide. The team uses lead zirconium titanate (Pb(Zr,Ti)O3), which, under the influence of an applied electric field, generates pathways parallel to the field. Consequently, as a result of polarization, some of the atoms travel “up” or “down”, thus creating conductive pathways – known as “walls” – in between the polarized zones. Up until now, the technology needed to control the process, via which these walls are formed, was unavailable.
In order to create flexible and reconfigurable circuits, the scientists use a ferroelectric material sandwiched between two specially-designed platinum electrodes. This technique allows them to regulate the direction in which the conductive pathways are formed, by applying specific voltage. The low conductivity of the electrodes ensures that the applied charges take quite some time to spread through the entire material, thereby enabling the team to control the exact location of the applied voltage. Speaking about the research, Dr. Leo McGilly at EPFL said:
By applying electric fields locally on the metal part, we were able to create pathways at different sites and move them, and also to destroy them with a reverse electric field. When we use highly conductive materials, the charge spreads rapidly and walls form randomly in the material.
With the help of this technology, the researchers have successfully managed to develop electric pathways at the atomic level. Each of these flexible circuits is capable of performing multiple tasks by simply reorganizing its various pathways. This property could likely lead to the growth of smart, multi-functional miniature electronic devices. Furthermore, these circuits can theoretically repair damaged pathways, without any effect on their performance. Dr. McGilly said:
[This technology is] an effective way to keep faulty devices working when they are in hard-to-reach places, like space.
Currently the team is working towards developing a prototype of the reconfigurable electronic circuits. Although the research is still in its nascent stage, the scientists are hopeful about its future prospects. Dr. McGilly said:
The fact that we can generate pathways wherever we want could allow us to imitate in the future phenomena that take place inside the brain, with the regular creation of new synapses. This could prove useful in reproducing the phenomenon of learning in an artificial brain.