XTPL Ultraprecise Deposition Technology for Advanced Printed µElectronics Applications

The Ultraprecise Deposition (UPD) technology is a novel additive manufacturing technique for advanced Printed µElectronics applications. UPD can be used for fabricating micrometer-size interconnections in microelectronic systems, as well as for making redistribution layers on chips and filing vias in semiconductor devices.
UPD may be considered as a much-needed intermediary approach between printing of 2D planar structures and free-standing 3D architectures. This technology gives the ability to print metallic structures at micrometer scale on complex substrates, so that the printed features map the topography of the substrate. The UPD approach is based on a direct extrusion of highly-concentrated silver paste using a printing nozzle with the diameter in the range from 0.5 to 10 𝜇m. This defines the unique operating range for the UPD technology, compared to other printed electronics techniques: the combination of high-viscosity pastes and fine printed features. The process itself is governed by pressure, but the possibility to extrude such high-viscosity materials using such narrow nozzles is possible thanks to the simultaneous optimization of the paste, parameters of the process, as well as the printing nozzle (both in terms of the geometry and material properties).
The key advantage of using the high-viscosity pastes is that the printed structures preserve their shape regardless of the wetting properties of the substrates. Therefore, the design of a metallization scheme is not constrained by the surface properties. The printed feature size can be in the range from 1 to 10 𝜇m and the printing resolution (i.e., the distance between the printed structures) can be even below 1 𝜇m.
The structures can be printed on complex substrates, including substrates with pre-existing features (like steps), substrates with different surface properties, as well as flexible substrates. The resulting printed structures can be bent and are uniform regardless of the wetting properties of the substrates. Therefore, it is possible to print on materials like oxides (e.g., SiO2), nitrides (e.g., SiNx), metals, glass, and foils (e.g., PI, Kapton), as well as to print on junctions (metal/semiconductor/insulator).