Design and electromechanical analysis of a novel Kirigami-patterned circuit substrate for high stretchability

Purpose This study aims to enhance the stretchability and electrical stability of flexible silver interconnects by integrating Kirigami-inspired structures into Polyimide (PI) substrates. The goal is to establish quantitative design rules that address multi-directional mechanical loads in wearable and deformable electronics. Design/methodology/approach A combined approach of experimental tensile testing, nonlinear finite element simulation, and response surface methodology is used. Screen-printed silver traces on Kirigami-patterned PI substrates are optimized by varying geometric and material parameters to reduce plastic strain and resistance variation. Findings Wavy Kirigami slits significantly lower plastic strain without increasing electrical resistance. A 16-wave, 0.20 mm amplitude slit reduces strain to 3.53% under 15% elongation. An optimized layout achieves less than 10% resistance growth and below 6.3% strain in both X and Y directions. Originality/value This work provides a comprehensive and validated design framework linking structural geometry with mechanical-electrical behavior. It offers practical design rules for stretchable electronics in wearable sensors and soft robotics, addressing real-world bidirectional deformation, a gap not sufficiently covered in prior studies.