The days of electronic chips becoming useless when they develop a small fault could be numbered. Researchers at the University of Illinois have developed a system that could allow chips to self-heal physical damage.
While integrated chips are a great space-saver and ideal for portable electronic devices, they currently have an inherent problem: if one part fails, the whole thing is done simply because even if you had the equipment to carry out a physical fix on such a tiny scale, it’s usually difficult or even impossible to get access without breaking the chip further.
The researchers took a system they had used for self-healing polymers and figured that given an electronic circuit is still a physical object, the technique should be transferrable.
While the application is complex, the principle of the technique is remarkably simple. It involves filling microcapsules, each around 10 microns (one-hundredth of a millimetre) in diameter, with a liquid metal. These capsules are then placed on top of the gold connections on the circuit board at regular intervals.
The idea is that any force that is strong enough to crack part of the circuit will also be enough to burst open the nearest capsule. The liquid metal then flows out and fills the crack in the circuit, quickly setting and re-establishing the connection. Tests showed that in 90 percent of cases, the chip could “heal” and regain 99 percent of its original level of conductivity.
The system has a couple of key advantages for practicality. It doesn’t require human intervention to locate the source of a fault: indeed, users may never even know there’s been a problem. And only the necessary microcapsules will burst open, meaning that the chip can work through multiple fractures as long as they don’t happen in exactly the same place twice.
The researchers say the next step is to see if the same system could work in other settings. They’ve proposed potential uses as diverse as a self-healing battery and large scale circuitry such as in planes or even spacecraft.