Highly stretchable and flexible kirigami patterned silver electrodes for wearable electronics

The next-generation wearable devices require highly stretchable and stable conductive electrodes. Accordingly, in this study, kirigami patterned silver electrodes were designed using finite element analysis (FEA) simulation to obtain an outstanding stretchable structure. Silver patterned electrodes have excellent stretchability owing to utilizing metamaterials and implementing specific patterning. Patterned Ag electrodes were fabricated on flexible polyurethane (PU) substrate, which showed acceptable stretching results at higher strains than Ag electrodes without any pattern. The resistance change (ΔR/R₀) during the stretching test was less than 7, when the electrode was stretched up to 50 % strain. In addition to stretching, other mechanical tests, such as the stretching fatigue, bending fatigue, rolling, folding, and twisting tests, were conducted, exhibiting less change in resistance which indicates the durability of the kirigami patterned Ag architecture for manufacturing stretchable electrodes which are applicable to wearable sensors. The patterned silver electrodes developed in this study were used as a wearable temperature sensor and a stretchable interconnector. A wearable temperature sensor with patterned electrode was produced to assess the temperature-sensing properties of the proposed electrode architecture with resistance changes for human wearable applications. In addition, a stretchable interconnector examines its performance when connected to a light emitting diode.