A Spider-Web-Like Highly Expandable Sensor Network for Multifunctional Materials
✍ Scribed by Giulia Lanzara; Nathan Salowitz; Zhiqiang Guo; Fu-Kuo Chang
- Book ID
- 102691414
- Publisher
- John Wiley and Sons
- Year
- 2010
- Tongue
- English
- Weight
- 965 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0935-9648
No coin nor oath required. For personal study only.
✦ Synopsis
The skin of living animals is an inspiration for the next generation of materials, devices, and structures. Human skin is sensitive to pressure, strain, and temperature; [ 1 , 2 ] dolphins or bats drastically reduce drag by sensing fl uid fl ow [3][4][5] and adapting either their skin shape [ 6 , 7 ] or rigidity; [ 8 ] and snakes use their skin to detect vibrations. [ 9 ] The fundamental common factor in these examples is that the living tissue is integrated with a network of distributed nano-or microscale sensors and actuators. To mimic such systems, novel materials and devices, such as paperlike displays, [10][11][12] biomedical electronics, [ 13 ] intelligent textiles, [ 14 ] artifi cial skin, [15][16][17] morphing materials, [ 18 ] robotics, wired or wireless sensor networks, and structural health monitoring systems, [ 19 ] should be integrated with distributed networks of miniaturized sensors and advanced electronics that span large macroscopic areas. The core problem in producing such networks is the current inability to integrate millions of microscale devices in precise predefi ned locations on a large macroscopic scale and to do so at reasonable cost. Common technologies for large-area electronics are based on manually assembling numerous individual and relatively large components into networks that cover large areas, but this is invasive to the material and/or structure and prohibitively expensive. New technologies like fl uidic self-assembly of silicon dies, [ 20 , 21 ] stretchable silicon, [ 22 , 23 ] stretchable metal interconnects, [24][25][26][27][28] or highly stretchable two-dimensional silicon wired networks [ 29 ] show promise, but have signifi cant drawbacks including wiring, [ 20 , 21 ] integration into structures, [ 20 , 21 , 29 ] invasive nature, [ 22 , 24 , 25 , 27 , 28 ] low expandability, [22][23][24][25][26][27][28] lack of mechanical fl exibility, [ 29 ] handling diffi culties, [ 20 , 21 , 29 ] and fi nally low temperature resistance, [ 22 , 23 ] which limit the types of applications. An effective multiscale method is required to overcome these issues. An innovative technology [ 30 ] consists of fabricating highly expandable, fl exible, and conductive substrates by forming a polyimide layer as a network of microscale wires and nodes. Here, we generalize the major fi ndings and extend this multiscale and cost-effective concept, [ 30 ] which can be used to integrate thousands of wired or wireless sensing elements into macroscopic material noninvasively. The key concept relies on the fact that by properly removing unnecessary material (99.7%) from a microscale polyimide thin fi lm hosting a network of thousands of devices, the network can be greatly expanded at low strain levels to cover large macroscopic areas. The expansion is characterized by area dilatations that are several orders of magnitude higher than those demonstrated to date in the literature.