Featured Research

from universities, journals, and other organizations

Mystery of the printed diode solved

Date:
July 7, 2014
Source:
Linköping Universitet
Summary:
A thirteen-year-long mystery that has involved a long series of researchers has finally been solved. A new article presents a diode in printed electronics that works in the GHz band, which opens up a new opportunity to send signals from a mobile phone to, for example, printed electronic labels. Energy from the radio signal is collected and used to switch the label's display. The diode being printed means that it is both cheap and simple to manufacture. Researchers have long known that the diode works, but not how and why.

GHz diode3_515.
Credit: Image courtesy of Linköping Universitet

With an article published in the Proceedings of the National Academy of Sciences in the United States of America (PNAS), a thirteen-year-long mystery that has involved a long series of researchers at both Linköping University and Acreo Swedish ICT has finally been solved.

The article presents a diode in printed electronics that works in the GHz band, which opens up a new opportunity to send signals from a mobile phone to, for example, printed electronic labels. Energy from the radio signal is collected and used to switch the label's display. The diode being printed means that it is both cheap and simple to manufacture.

"This means that we can supply power to printed electronics within the 'internet of things' with the help of conventional mobile phones. This gives us new opportunities for communications," says Negar Sani, PhD student at the Laboratory for Organic Electronics at Linköping University.

Researchers have long known that the diode works, but not how and why.

In 2001, Petronella Norberg at Acreo Swedish ICT, laid a disc of silicon in a mortar, ground it down and produced a silicon paste that she then used as ink in a printing press. She produced a functional printed diode -- the electronic key component that, among other things, converts alternating current to direct current. But the diode only worked up to 1 MHz, and no immediate field of use could be found.

At Acreo Swedish ICT, a research team funded by the British company De La Rue, worked for several years on developing both the diode and new printing pastes. With a paste containing the transition metal niobium, in the form of niobium silicide, NbSi2, printed over the silicon paste, they got the whole thing to work at GHz as well.

"The results meant a world record for printed diodes, and we were also able to manufacture a demonstrator for De La Rue where the signal from a mobile phone was used to activate a printed display. We had demonstrated that it was possible to link paper to the Internet," says Göran Gustafsson, department head at Acreo Swedish ICT.

But still nobody knew how the diode worked.

Ms Sani has now taken the last decisive step toward solving the puzzle, naturally with the help of Professors Magnus Berggren and Xavier Crispin as well as Senior Lecturer and Project Manager Isak Engquist, and a number of people at Acreo Swedish ICT. The results of Ms Sani's work showed that it must have to do with tunnel effects, a phenomenon in quantum physics that makes it so that particles can get past obstacles. In this case, nano-thin films (1-10 2 nm) are formed around the micrometer-sized grains of silicon, where the current between anodes (aluminium) and cathodes (silver and carbon) pass through, but only in one direction.

Thirteen years of work got an explanation -- one that the editorial board of PNAS finally approved after more than five months of hard review by experts from various fields.

"This is the longest project I've worked on. What research sponsor wants to wait 13 years for publication? Without industry -- De La Rue, in this case -- we'd never have come this far. Now printed electronics are starting to get the same performance as traditional electronics, and this is another example of the fruitful combination of our research, developments at Acreo and needs from the industry," says Magnus Berggren, professor of Organic Electronics at Linköping University.


Story Source:

The above story is based on materials provided by Linköping Universitet. Note: Materials may be edited for content and length.


Journal Reference:

  1. Negar Sani, Mats Robertsson, Philip Cooper, Xin Wang, Magnus Svensson, Peter Andersson Ersman, Petronella Norberg, Marie Nilsson, David Nilsson, Xianjie Liu, Hjalmar Hesselbom, Laurent Akesso, Mats Fahlman, Xavier Crispin, Isak Engquist, Magnus Berggren, and Göran Gustafsson. All-printed diode operating at 1.6 GHz. PNAS, July 7, 2014 DOI: 10.1073/pnas.1401676111

Cite This Page:

Linköping Universitet. "Mystery of the printed diode solved." ScienceDaily. ScienceDaily, 7 July 2014. <www.sciencedaily.com/releases/2014/07/140707161612.htm>.
Linköping Universitet. (2014, July 7). Mystery of the printed diode solved. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2014/07/140707161612.htm
Linköping Universitet. "Mystery of the printed diode solved." ScienceDaily. www.sciencedaily.com/releases/2014/07/140707161612.htm (accessed August 22, 2014).

Share This




More Matter & Energy News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Is It a Plane? No, It's a Hoverbike

Is It a Plane? No, It's a Hoverbike

Reuters - Business Video Online (Aug. 22, 2014) — UK-based Malloy Aeronautics is preparing to test a manned quadcopter capable of out-manouvering a helicopter and presenting a new paradigm for aerial vehicles. A 1/3-sized scale model is already gaining popularity with drone enthusiasts around the world, with the full-sized manned model expected to take flight in the near future. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Coal Gas Boom in China Holds Climate Risks

Coal Gas Boom in China Holds Climate Risks

AP (Aug. 22, 2014) — China's energy revolution could do more harm than good for the environment, despite the country's commitment to reducing pollution and curbing its carbon emissions. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Newsy (Aug. 21, 2014) — Researchers found the scanners could be duped simply by placing a weapon off to the side of the body or encasing it under a plastic shield. Video provided by Newsy
Powered by NewsLook.com
Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) — Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins