A medical robotic hand is just one potential application for the new rubbery semiconductor material. Image: University of Houston.
A medical robotic hand is just one potential application for the new rubbery semiconductor material. Image: University of Houston.

A medical robotic hand could allow doctors to accurately diagnose and treat people from halfway around the world. But currently available technologies aren't good enough to match the in-person experience.

Now, in a paper in Science Advances, a team of researchers in the US report that they have designed and produced a smart electronic skin and a medical robotic hand capable of assessing vital diagnostic data by using a newly invented rubbery semiconductor with high carrier mobility. According to Cunjiang Yu, associate professor of mechanical engineering at the University of Houston (UH) and corresponding author of the paper, this rubbery semiconductor material can also be easily scaled for manufacturing, thanks to a new interfacial fabrication method.

This all suggests a pathway toward soft, stretchy rubbery electronics and integrated systems that mimic the mechanical softness of biological tissues. Such rubbery electronics could be suitable for a variety of emerging applications, said Yu, who also is a principal investigator at the Texas Center for Superconductivity at UH. The smart skin and medical robotic hand are just two potential applications, created by the researchers to illustrate the discovery's utility.

Traditional semiconductors are brittle, and using them in otherwise stretchable electronics has required special mechanical accommodations. Previous stretchable semiconductors have had drawbacks of their own, including low carrier mobility – the speed at which charge carriers can move through a material – and complicated fabrication requirements.

Last year, Yu and his collaborators reported that adding minute amounts of metallic carbon nanotubes to the polymer semiconductor P3HT (polydimethylsiloxane composite) improves carrier mobility, which governs the performances of semiconductor transistors. Now, they've gone on to develop a scalable manufacturing method for these high-performance stretchable semiconducting nanofilms and to create fully rubbery transistors, which represents a significant step forward.

The production is simple. A commercially available semiconductor material is dissolved in a solvent and dropped on water, where it spreads; the chemical solvent then evaporates from the solution, resulting in improved semiconductor properties. It is a new way to create high-quality composite films, Yu said, allowing for consistent production of fully rubbery semiconductors.

This rubbery semiconductor material retains its electrical performance even when stretched by 50%, which is a notable advance. Human skin, Yu said, can be stretched by only about 30% without tearing.

This story is adapted from material from the University of Houston, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.