Fabrication of Ag circuit embedded in PDMS substrate and its mechanical and electrical property with variations of photonic energy

Highlights: • Embedding of metal nanoparticles in PDMS substrate was devised. • Ag nanoparticles were sintered at various photonic energy conditions and they show the microstructural evolution. • Increased electrical conductivity and ECM lifetime of Ag circuit with increasing photonic energy were identified. Ag circuit embedded in polydimethylsiloxane (PDMS) substrate were fabricated through photonic sintering and transfer of Ag nanoparticles (NPs) for reducing processing time, cost, damage to the substrate, and delamination caused by the low surface energy of PDMS. The photonic energy led to the microstructural evolution of a printed Ag circuit by rapid cluster formation and by removing the organics within several microseconds. Variations of surface roughness showed increasing trends at higher photonic energy conditions and drastic decrease after the embedding process. Hardness and electrical resistivity were measured before and after PDMS embedding, and after the second photonic sintering at various photonic energy conditions. The Ag circuit embedded in the PDMS substrate showed improved hardness by 207% due to the denser microstructure of the flipped surface and increased electrical resistivity increasing by 54% on average. Moreover, the effects of second sintering on the microstructure, electrical, and mechanical properties and the electrochemical reliability of the embedded Ag circuit are also studied.