Defying the term hardware, electrical engineers and materials scientists have developed electronic circuits that can bend, extend, and even twist into a spiral. Their design features small electronic elements embedded in silicone rubber and connected by bridges that change shape to accommodate strain when the surrounding material stretches. “Strain is what kills electronics,” says Yonggang Huang, a Northwestern University engineer with the team that developed the circuits.
Most existing electronics, such as the circuit boards in everything from mobile devices to solar cells, are built on brittle silicon wafers. These must be protected by solid casings, limiting the surfaces and environments where devices can be placed. With the new elasticity, electronics could be attached to curved surfaces that warp and undulate, such as the human body. And since the circuits are surrounded by biofriendly silicone, they could also be used in implantable heart and brain monitors, says codeveloper John Rogers, a materials scientist at the University of Illinois at Urbana-Champaign. “We can now wrap silicon-based technology around all kinds of objects,” Rogers says. Other possibilities include a flexible heart monitor that conforms to an athlete’s moving body and wearable solar cells.