Advance in contact printing could lead to bendable electronics

Engineers in Scotland have created a contact-printing system that embeds silicon nanowires into flexible surfaces, an advance that could lead to new forms of bendable electronics.

bendable electronics

In a paper published in Microsystems and Nanoengineeringengineers from Glasgow University describe how they have fabricated high-mobility semiconductor nanowires onto flexible surfaces to develop what are claimed to be high-performance ultra-thin electronic layers.

Those surfaces, which can reportedly be bent, flexed and twisted, could be utilised in video screens, improved health monitoring devices, implantable devices and synthetic skin for prosthetics.

The advance has been made at Glasgow University’s Bendable Electronics and Sensing Technologies (BEST) research group, which is led by Prof Ravinder Dahiya.

The BEST team has already developed solar-powered, flexible ‘electronic skin’ for use in prosthetics and stretchable health sensors that monitor pH levels of users’ sweat.

In their latest paper, the research team outline how they manufactured semiconductor nanowires from silicon and zinc oxide and printed them on flexible substrates to develop electronic devices and circuits.

In the process, they discovered that they could produce uniform silicon nanowires which aligned in the same direction, compared to what Glasgow University describes as the more random, tree-branch-like arrangement produced by a similar process for zinc oxide.

The team then engaged in a series of experiments to print the wires into flexible surfaces with a printing device they developed and built in their lab. After a series of experiments, they were able to find the optimal combination of pressure and velocity to print the nanowires repeatedly.

Prof Dahiya said: “This paper marks a really important milestone on the road to a new generation of flexible and printed electronics. In order for future electronic devices to integrate flexibility into their design, industry needs to have access to energy-efficient, high-performance electronics which can be produced affordably and over large surface areas.

“With this development, we’ve gone a long way to hitting all of those marks. We’ve created a contact-printing system which allows us to reliably create flexible electronics with a high degree of reproducibility, which is a really exciting step towards creating all kinds of bendable, flexible, twistable new devices.

“We’ve just secured further funding which we’ll use to scale up the process further, making it more readily applicable to industrial purposes, and we’re looking forward to building on what we’ve managed to achieve already.”

The research was supported by funding from EPSRC.