Info
Info

Stanford Researchers Develop Stretchable, Touch-sensitive Electronics

 
A pixelated electronic sensor built with skin-like materials conforms to a palm. (Image credit: L.A. Cicero)

Stanford researchers have set the stage for an evolution in electronics by taking the concept of ‘artificial skin’ to the next level, demonstrating not only a stretchable circuitry that can feel the touch of a ladybug, but a manufacturing process to mass produce this circuitry. By Andrew Myers and Tom Abate

Of the many ways that humans make sense of our world – with our eyes, ears, nose and mouth – none is perhaps less appreciated than our tactile and versatile hands. Thanks to our sensitive fingertips, we can feel the heat before we touch the flame, or sense the softness of a newborn’s cheek.

But people with prosthetic limbs live in a world without touch. Restoring some semblance of this sensation has been a driving force behind Stanford chemical engineer Zhenan Bao’s decades-long quest to create stretchable, electronically-sensitive synthetic materials. Such a breakthrough could one day serve as skin-like coverings for prosthetics. But in the near term, this same technology could become the foundation for the evolution of new genre of flexible electronics that are in stark contrast with rigid smartphones that many of us carry, gingerly, in our back pockets.

In a Feb. 19 Nature paper, Bao and her team describe two technical firsts that could bring this 20-year goal to fruition: the creation of a stretchable, polymer circuitry with integrated touch-sensors to detect the delicate footprint of an artificial ladybug. And while this technical achievement is a milestone, the second, and more practical, advance is a method to mass produce this new class of flexible, stretchable electronics – a critical step on the path to commercialization, Bao said.

“Research into synthetic skin and flexible electronics has come a long way, but until now no one had demonstrated a process to reliably manufacture stretchable circuits," Bao said.

Bao’s hope is that manufacturers might one day be able to make sheets of polymer-based electronics embedded with a broad variety of sensors, and eventually connect these flexible, multipurpose circuits with a person’s nervous system. Such a product would be analogous to the vastly more complex biochemical sensory network and surface protection “material" that we call human skin, which can not only sense touch, but temperature and other phenomena, as well. But long before artificial skin becomes possible, the processes reported in this Nature paper will enable the creation of foldable, stretchable touchscreens, electronic clothing or skin-like patches for medical applications.

Bao said their production process involves several layers of new-age polymers, some that provide the material’s elasticity and others with intricately patterned electronic meshes. Still, others serve as insulators to isolate the electronically sensitive material. One step in the production process involves the use of an inkjet printer to, in essence, paint on certain layers.

“We’ve engineered all of these layers and their active elements to work together flawlessly," said post-doctoral scholar Sihong Wang, co-lead author of the paper.

The team has successfully fashioned its material in squares about two inches on a side containing more than 6,000 individual signal-processing devices that act like synthetic nerve endings. All this is encapsulated in a waterproof protective layer.

The prototype can be stretched to double its original dimensions – and back again – all the while maintaining its ability to conduct electricity without cracks, delamination or wrinkles. To test durability, the team stretched a sample more than one thousand times without significant damage or loss of sensitivity. The real test came when the researchers adhered their sample to a human hand.

“It works great, even on irregularly shaped surfaces," said postdoctoral scholar Jie Xu, and the paper’s other co-lead author.

Perhaps most promising of all, the fabrication process described in this paper could become a platform for evaluating other stretchable electronic materials developed by other researchers that could one day begin to replace today’s rigid electronics.

Bao said much work lies ahead before these new materials and processes are as ubiquitous and capable as rigid silicon circuitry. First up, she said, her team must improve the electronic speed and performance of their prototype, but this is a promising step.

“I believe we’re on the verge of a whole new world of electronics," Bao said.

This research was supported by Samsung Electronics, the National Science Foundation Graduate Research Fellowship Program, and NETEP and MOTIE of the Republic of Korea.

Infineon Adds 200 V Half-bridge Gate Driver IC For Reliable Start-up Operation
NXP Acquires OmniPHY To Accelerate Autonomous Driving And Vehicle Networks
NanoScientific Symposium On Scanning Probe Microscopy (SPM)
Sensirion Announce Strong Revenue Growth In First Half-year 2018
Helium Leak Detector Solutions
VTT Is Ranked Fourth In The World's Largest Research Funding Programme
Healthcare Transformation: A Business Opportunity For BioMEMS
Palomar Technologies Awarded ISO 9001:2015 Certificate
KLA-Tencor Expands IC Packaging Portfolio
UGent And Imec Launch Fiber Optic Sensing Spin-off Sentea
Imec.xpand Raises EUR 117 Million To Invest In Innovative, Early-stage Ideas
Himax Technologies Rebukes Motley Fool Article
Murata Invests In MEMS Sensor Manufacturing
Brewer Science Announces RDL-first Fan-out Packaging Material
China’s Semiconductor Fab Capacity To Reach 20 Percent Worldwide Share In 2020
SiTime And Bosch Accelerate Innovation In MEMS Timing For 5G And IoT
GLOBALFOUNDRIES Reshapes Technology Portfolio To Focus On Differentiated Offerings
Chroma Offers Semiconductor Test Solutions
Rudolph Technologies Launches Second-gen Inspection And Metrology System
New Material Could Improve Efficiency Of Computer Processing And Memory
Teledyne E2v’s Emerald 12M And 16M Image Sensors Enter Mass Production
Nova's Materials Metrology Solution Selected For 5nm Technology Node
Infineon Expands U.S.-based IoT Security Research And Development Programs
Thermco Systems Expands Global Operations With Acquisition Of CSD Epitaxy

Info
×
Search the news archive

To close this popup you can press escape or click the close icon.
Logo
×
Logo
×
Register - Step 1

You may choose to subscribe to the Silicon Semiconductor Magazine, the Silicon Semiconductor Newsletter, or both. You may also request additional information if required, before submitting your application.


Please subscribe me to:

 

You chose the industry type of "Other"

Please enter the industry that you work in:
Please enter the industry that you work in:
 
X
Info
X
Info