Stretchable electronic strips for electronic textiles enabled by 3D helical structure– www.nature.com

The fabrication process is illustrated in Fig. 2. A ‘strip’, having length much greater than its width, was fabricated on PI film (“the planar e-strip”). Components were soldered onto the planar e-strip, and adhesive encapsulation was added. Figure 2B shows one end of the e-strip (or both, depending on design) containing solder pads for connectors to be attached, and angled so that the connector is aligned with the core of the helical e-strip. This is matched to the desired helix angle of the helical e-strip. Planar e-strips were fabricated in batches on an adhesive tape carrier, using etching processes to selectively remove copper from copper-plated PI (Fig. 2B,C). E-strips were then wrapped around a rubber core and bonded in place with adhesive, forming the stretchable helical structure in Fig. 2D.