|The Human Touch: Stretchable Electronic Skin Can “Feel”|
After over two decades of focused effort, a large, multidisciplinary team based at Stanford University, led by chemical engineer Zhenan Bao, has developed a “skin” using an array of thousands of transistors—and recently demonstrated its flexibility and ruggedness.
Their paper “Skin electronics from scalable fabrication of an intrinsically stretchable transistor array” published in Nature, plus the detailed Supplementary Information packet, provides details on the concept, design, fabrication, and performance. (The project is supported by Samsung Electronics, the National Science Foundation Graduate Research Fellowship Program, and NETEP and MOTIE of the Republic of Korea.)
The sensing skin is based on intrinsically stretchable polymer materials, a relatively new technology. The team developed a transistor matrix with an unprecedented device density for this class of materials of 347 transistors per square centimeter (note the order-of-magnitudes difference between this density figure and even an early-generation IC). The team produced square devices that are about two inches (5 cm) on a side and contain more than 6,000 individual signal-processing devices acting like synthetic nerve endings, all fully encapsulated in a waterproof protective layer…