Abstract
The development of flexible electronics with bending and stretchability capabilities that enable compact and simplified designs is an active research field because of their wide potential applications, such as flexible sensors, soft robotics, and space-related systems. However, repeated loads and deformations cause electrode disconnections, leading to device malfunctions. One solution is to use a self‑healing microstrip line that repairs cracks through metallic nanoparticle bridging induced by a dielectrophoretic force. While previous studies have focused on terrestrial applications under atmospheric conditions, this study employs a low-volatility dispersion for the self‑healing microstrip line system, enabling its operation in a vacuum. A self‑healing system utilizing a perfluoropolyether (PFPE) oil dispersion containing copper nanoparticles was tested under both atmospheric and vacuum conditions. The developed dispersion, which has a low vapor pressure and high insulation, successfully repaired deliberately disconnected gold microstrip lines in both environments. Bubbles, which are assumed to originate from air adsorbed on the particle surfaces and dissolved in PFPE, formed during the repair process, disturbing the stabilization of the particle bridge and hindering the repair. However, the vacuum environment facilitated degassing, thereby enhancing the repair performance.