Direct integration of dielectric all-ceramic thick films on a polymer substrate using room temperature fabrication

Direct integration of all-ceramic thick films and a polymer substrate has been realized for the first time without high temperature processing using the Room Temperature Fabrication method.Printable Li₂MoO₄-BaTiO₃ composite pastes with 0, 10, and 20 vol.% of BaTiO₃ were fabricated from the respective ceramic powders and water without organic additives or vehicles. The pastes were stencil printed on a polyimide substrate and dried at 120 °C without pressing or lamination.Using scanning electron microscopy, the films were observed to be in seamless contact with the substrate and to have a uniform microstructure. Relative permittivities of the ceramic films increased from 4.2 to 7.2 (at 2.5 GHz) and 4.5 to 7.5 (at 9.9 GHz) according to the vol.% content of the added BaTiO₃, with corresponding dielectric losses from 10⁻³ to 10^-2.The results show that the room temperature fabrication method enables 2D printing of all-ceramic thick films on temperature-sensitive substrates.