Utilizing the Cold Sintering Process for Flexible-Printable Electroceramic Device Fabrication

Conventional thermal sintering of ceramics is generally accomplished at high temperatures in kilns or furnaces. We have recently developed a procedure where the sintering of a ceramic can take place at temperatures below 200 degrees C, using aqueous solutions as transient solvents to control dissolution and precipitation and enable densification (i.e., sintering). We have named this approach as the "Cold Sintering Process" because of the drastic reduction in sintering temperature and time relative to the conventional thermal process. In this study, we fabricate basic monolithic capacitor array structures using a ceramic paste that is printed on nickel foils and polymer sheets, with silver electrodes. The sintered capacitors, using a dielectric Lithium Molybdenum Oxide ceramic, were then cold sintered and tested for capacitance, loss, and microstructural development. Simple structures demonstrate that this approach could provide a cost-effective strategy to print and densify different materials such as ceramics, polymers, and metals on the same substrate to obtain functional circuitry.