Researchers make new electronics -- with a twist

November 19, 2008

They've made electronics that can bend. They've made electronics that can stretch.

And now, they've reached the ultimate goal -- electronics that can be subjected to any complex deformation, including twisting.

Yonggang Huang, Joseph Cummings Professor of Civil and Environmental Engineering and Mechanical Engineering at Northwestern University's McCormick School of Engineering and Applied Science, and John Rogers, the Flory-Founder Chair Professor of Materials Science and Engineering at the University of Illinois at Urbana-Champaign, have improved their so-called "pop-up" technology to create circuits that can be twisted. Such electronics could be used in places where flat, unbending electronics would fail, like on the human body.

Their research is published online by the Proceedings of the National Academy of Sciences (PNAS).

Electronic components historically have been flat and unbendable because silicon, the principal component of all electronics, is brittle and inflexible. Any significant bending or stretching renders an electronic device useless.

Huang and Rogers developed a method to fabricate stretchable electronics that increases the stretching range (as much as 140 percent) and allows the user to subject circuits to extreme twisting. This emerging technology promises new flexible sensors, transmitters, new photovoltaic and microfluidic devices, and other applications for medical and athletic use.

The partnership -- where Huang focuses on theory, and Rogers focuses on experiments -- has been fruitful for the past several years. Back in 2005, the pair developed a one-dimensional, stretchable form of single-crystal silicon that could be stretched in one direction without altering its electrical properties; the results were published by the journal Science in 2006. Earlier this year they made stretchable integrated circuits, work also published in Science.

Next, the researchers developed a new kind of technology that allowed circuits to be placed on a curved surface. That technology used an array of circuit elements approximately 100 micrometers square that were connected by metal "pop-up bridges."

The circuit elements were so small that when placed on a curved surface, they didn't bend -- similar to how buildings don't bend on the curved Earth. The system worked because these elements were connected by metal wires that popped up when bent or stretched. The research was the cover article in Nature in early August.

In the research reported in PNAS, Huang and Rogers took their pop-up bridges and made them into an "S" shape, which, in addition to bending and stretching, have enough give that they can be twisted as well.

"For a lot of applications related to the human body -- like placing a sensor on the body -- an electronic device needs not only to bend and stretch but also to twist," said Huang. "So we improved our pop-up technology to accommodate this. Now it can accommodate any deformation."

Huang and Rogers now are focusing their research on another important application of this technology: solar panels. The pair published a cover article in Nature Materials this month describing a new process of creating very thin silicon solar cells that can be combined in flexible and transparent arrays.
-end-


Northwestern University

Related Engineering Articles from Brightsurf:

Re-engineering antibodies for COVID-19
Catholic University of America researcher uses 'in silico' analysis to fast-track passive immunity

Next frontier in bacterial engineering
A new technique overcomes a serious hurdle in the field of bacterial design and engineering.

COVID-19 and the role of tissue engineering
Tissue engineering has a unique set of tools and technologies for developing preventive strategies, diagnostics, and treatments that can play an important role during the ongoing COVID-19 pandemic.

Engineering the meniscus
Damage to the meniscus is common, but there remains an unmet need for improved restorative therapies that can overcome poor healing in the avascular regions.

Artificially engineering the intestine
Short bowel syndrome is a debilitating condition with few treatment options, and these treatments have limited efficacy.

Reverse engineering the fireworks of life
An interdisciplinary team of Princeton researchers has successfully reverse engineered the components and sequence of events that lead to microtubule branching.

New method for engineering metabolic pathways
Two approaches provide a faster way to create enzymes and analyze their reactions, leading to the design of more complex molecules.

Engineering for high-speed devices
A research team from the University of Delaware has developed cutting-edge technology for photonics devices that could enable faster communications between phones and computers.

Breakthrough in blood vessel engineering
Growing functional blood vessel networks is no easy task. Previously, other groups have made networks that span millimeters in size.

Next-gen batteries possible with new engineering approach
Dramatically longer-lasting, faster-charging and safer lithium metal batteries may be possible, according to Penn State research, recently published in Nature Energy.

Read More: Engineering News and Engineering Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.