Indium Semiconductor Used To Demonstrate Ultraflexible Electronics

Researchers at ETH Zurich are developing electronic components that are thinner and more flexible than before. They can even be wrapped around a single hair without damaging the electronics. This opens up new possibilities for ultra-thin, transparent sensors that are literally easy on the eye.

In Professor Gerhard Tröster’s Electronics Lab, scientists have been researching flexible electronic components, such as transistors and sensors, for some time now. The aim is to weave these types of components into textiles or apply them to the skin in order to make objects ‘smart’, or develop unobtrusive, comfortable sensors that can monitor various functions of the body.

The researchers have now taken a big step towards this goal and their work has recently been published in the journal Nature Communications. With this new form of thin-film technology, they have created a very flexible and functional electronics. The membrane consists of the polymer parylene. The parylene film has a maximum thickness of 0.001 mm, making it 50 times thinner than a human hair. In subsequent steps, they used standardised methods to build transistors and sensors from semiconductor materials, such as indium gallium zinc oxide, and conductors, such as gold. The researchers then released the parylene film with its attached electronic components from the wafer.

An electronic component fabricated in this way is extremely flexible, adaptable and – depending on the material used for the transistors – transparent. The researchers confirmed the theoretically determined bending radius of 50 micrometers during experiments in which they placed the electronic membrane on human hair and found that the membrane wrapped itself around the hair with perfect conformability. The transistors, which are less flexible than the substrate due to the ceramic materials used in their construction, still worked perfectly despite the strong bend.

Münzenrieder and Salvatore see ‘smart’ contact lenses as a potential area of application for their flexible electronics. In the initial tests, the researchers attached the thin-film transistors, along with strain gauges, to standard contact lenses. They placed these on an artificial eye and were able to examine whether the membrane, and particularly the electronics, could withstand the bending radius of the eye and continue to function. The tests showed, in fact, that this type of smart contact lens could be used to measure intraocular pressure, a key risk factor in the development of glaucoma.

Professor Tröster’s laboratory has already attracted attention in the past with some unusual ideas for wearable electronics. For example, the researchers have developed textiles with electronic components woven into them and they have also used sensors to monitor the bodily functions of Swiss ski jumping star Simon Ammann during his jumps.

Rosetta Space Probe to Land on Comet, Use Indium to Analyze Composition

After a ten-year journey and a long, deep sleep the Rosetta space probe was woken up on 20 January. The vehicle now starts the last leg of its journey which will lead it to the 67P/Churyumov-Gerasimenko comet. The Philae lander is to descend to the comet’s surface in November.

The climax of the mission: In November of this year the Philae lander, equipped with nine further experiments, will touch down on the surface of the comet – a first in the history of space travel.

The plan is for Rosetta to investigate this cometary material in more detail than ever before. “The space probe is a kind of laboratory that is operated on-site at the comet,” says Max Planck Researcher Martin Hilchenbach, Head of the COSIMA team. COSIMA is one of the instruments whose main task is to draw out some of the secrets of the cometary dust.

In the microscopic, cauliflower-shaped pores of carriers only a few millimetres in size, the cosmic dust catcher collects individual particles, which are initially localised under a microscope and then bombarded with indium ions. The ions, which are thus released from the surface of the dust particles, can then be analysed further. “In this way, we can identify not only individual elements, but also organic molecules in particular,” says Hilchenbach.

Researchers Create Copper Indium Selenide Solar Cells with Next Generation Efficiency Levels

Scientists at the U.S. Department of Energy’s Argonne National Laboratory and the University of Texas at Austin have together developed a new, inexpensive material that has the potential to capture and convert solar energy—particularly from the bluer part of the spectrum—much more efficiently than ever before.

Most simple solar cells handle these bluish hues of the electromagnetic spectrum inefficiently. Because of this limitation, scientists had originally believed that simple solar cells would never be able to convert more than about 34 percent of incoming solar radiation to electricity.

In their study, Korgel and his team used specialized spectroscopic equipment at Argonne’s Center for Nanoscale Materials to look at multiexciton generation in copper indium selenide, a material closely related to another more commonly produced thin film that holds the record for the most efficient thin-film semiconductor. “This is one of the first studies done of multiple exciton generation in such a familiar and inexpensive material,” said Argonne nanoscientist Richard Schaller.

The study mostly proves that the efficiency boost provided by multiple exciton extraction is possible in mass-producible materials.

“The holy grail of our research is not necessarily to boost efficiencies as high as they can theoretically go, but rather to combine increases in efficiency to the kind of large-scale roll-to-roll printing or processing technologies that will help us drive down costs,” Korgel said.

We have the items below currently available on eBay. Roll the mouse pointer over an image and click once to center the image in the row. Once centered, click the image to jump to the eBay listing.