Lee, Aram Kang, Minji Kim, Do Young Jang, Hee Yoon Park, Ji-Won Kim, Tae-Wook Hong, Jae-Min Lee, Seoung-Ki 2024-07-26T06:30:10Z 2024-07-26T06:30:10Z 2024-07-26 2024-07 1226-7945 https://pubs.kist.re.kr/handle/201004/150306 This study proposes an innovative methodology for developing flexible printed circuit boards (FPCBs) capable of conforming to three-dimensional shapes, meeting the increasing demand for electronic circuits in diverse and complex product designs. By integrating a traditional flat plate-based fabrication process with a subsequent three-dimensional thermal deformation technique, we have successfully demonstrated an FPCB that maintains stable electrical characteristics despite significant shape deformations. Using a modified polyimide substrate along with Ag flake-based conductive ink, we identified optimized process variables that enable substrate thermal deformation at lower temperatures (~130℃) and enhance the stretchability of the conductive ink (ε ~30%). The application of this novel FPCB in a prototype 3D-shaped sensor device, incorporating photosensors and temperature sensors, illustrates its potential for creating multifunctional, shape-adaptable electronic devices. The sensor can detect external light sources and measure ambient temperature, demonstrating stable operation even after transitioning from a planar to a three-dimensional configuration. This research lays the foundation for next-generation FPCBs that can be seamlessly integrated into various products, ushering in a new era of electronic device design and functionality. Korean 한국전기전자재료학회 Development of Three-Dimensional Deformable Flexible Printed Circuit Boards Using Ag Flake-Based Conductors and Thermoplastic Polyamide Substrates Article 10.4313/JKEM.2024.37.4.9 2 전기전자재료학회논문지, v.37, no.4, pp.420 - 426 전기전자재료학회논문지 37 4 420 426 N kci ART003095890 Flexible printed circuit boards 3D shape deformation Flake based Ag ink Thermal deformation processing Stretchable electronics