Chinese scientists have created fully flexible fiber chips with circuits that are integrated and embedded within stretchable strands as thin as human hair at a density rivaling those of a home computer’s central processing unit (CPU). This allows the fibers to compute like chips or display information like transistors, effectively enabling machine-washable cloth to work like a computer or television. The advance was published in the peer-reviewed journal Nature. The study was led by Peng Huisheng, Member of the Chinese Academy of Sciences (CAS) at Fudan University in Shanghai. The team developed a novel electronic device named a fiber integrated circuit (FIC). Instead of fabricating circuits on rigid planar substrates, the researchers built functional circuits on an elastic substrate, which was then rolled into a thin fiber resembling a scroll.
Although as thin as a strand of human hair, the fiber achieves a transistor density of 100,000 per centimeter, meeting the industry standard of traditional very large-scale integration (VLSI) while remaining fully flexible. According to Chen Peining from Fudan’s Institute of Fiber Materials and Devices and a corresponding author of the paper, at the present lab-scale photolithography precision of 1 micrometer, a 1 mm “fiber chip” could integrate tens of thousands of transistors, with an information-processing capacity comparable to that of certain medical implant chips. “Extending the fiber to 1 meter could raise the transistor count to the million level, approaching the integration scale of classical computer central processing units,” Chen said in a Fudan University report, adding that “nanometer-scale photolithography in the future would further increase integration density.” The fiber itself can function as a complete microcomputer system, achieving a high-precision interconnection of electronic components such as resistors, capacitors, diodes and transistors. The photolithography precision reaches the highest level of laboratory-grade photolithography machines, according to the report.
“FICs can process both digital and analogue signals similar to commercial arithmetic chips and perform neural computing with high recognition accuracy, matching the performance of state-of-the-art in-memory image processors,” the team wrote. The researchers said the FICs exhibited exceptional stability and durability under harsh conditions that bulky planar counterparts struggled to withstand, including 10,000 cycles of repeated bending and abrasion. The FICs could also stretch by up to 30%, twisting at 180 degrees per centimeter, as well as weather more than 100 washes, exposure to heat reaching 100 degrees Celsius and even compression under a 15.6-ton container truck, they added. Based on this work, the team pioneered the integration of power, sensing, computing and display functions into a single, independent FIC. This allows future smart clothing and devices to function without any bulky external chips or wires, the South China Morning Post reports.
