Scientists at the Department of Materials Engineering (DME), Indian Institute of Science (IISc), have developed a “super-flexible” composite semiconductor material with potential applications in curved displays, foldable phones and wearable electronics.
The material could replace traditional semiconductor devices used in display industries, like transistors, which are not flexible or strain-tolerant. There is also a limit to adding polymers to increase the flexibility of oxide semiconductors, without compromising the semiconductor’s performance, IISc said on Tuesday.
The researchers have, in a study published in Advanced Materials Technologies, identified ways to fabricate a composite containing polymer up to 40 per cent of the material weight, with inkjet printing. Previous studies have reported only up to 1-2 per cent polymer addition.
“Interestingly, the approach enabled the semiconducting properties of the oxide semiconductor to remain unaltered with the polymer addition. The added large quantity of polymer also made the composite semiconductor highly flexible and foldable without deteriorating its performance,” IISc said.
The composite semiconductor is made up of a water-insoluble polymer such as ethyl cellulose that provides flexibility, and indium oxide, a semiconductor that brings in “excellent electronic transport properties”.
A team led by Subho Dasgupta – Associate Professor in DME and corresponding author of the study – used inkjet printing, instead of traditional techniques in semiconductor material fabrication, to deposit their material onto various flexible substrates, from plastics to paper. The team has obtained a patent for the material.
Special functional inks are used to print electronic components on surfaces.
First author Mitta Divya, former PhD student at DME and a postdoc at King Abdullah University of Science and Technology, Saudi Arabia, said the team had optimised protocols to ensure a continuous and homogeneous film.
Dasgupta said such low-cost, easy-to-manufacture printed semiconductors could be used to fabricate fully printed and flexible television screens, wearables, and large electronic billboards.