Micro Embossing of Ceramic Green Substrates for Micro Devices

TL;DR

This paper presents a micro embossing process for creating high-fidelity micro features on ceramic green substrates, enabling embedded micro channels for advanced electronic and microfluidic applications.

Contribution

It introduces an optimized micro embossing technique on ceramic green tapes with near-zero shrinkage, achieving micro features as small as a few micrometers.

Findings

Micro features with line-widths of a few micrometers were successfully embossed.

Extending holding time at certain temperatures hardens green substrates without affecting fidelity.

Embedded micro channels were successfully formed after co-firing.

Abstract

Multilayered ceramic substrates with embedded micro patterns are becoming increasingly important, for example, in harsh environment electronics and microfluidic devices. Fabrication of these embedded micro patterns, such as micro channels, cavities and vias, is a challenge. This study focuses on the process of patterning micro features on ceramic green substrates using micro embossing. A ceramic green tape that possessed near-zero shrinkage in the x-y plane was used, six layers of which were laminated as the embossing substrate. The process parameters that impact on the pattern fidelity were investigated and optimized in this study. Micro features with line-width as small as several micrometers were formed on the ceramic green substrates. The dynamic thermo-mechanical analysis indicated that extending the holding time at certain temperature range would harden the green substrates with little effect on improving the embossing fidelity. Ceramic substrates with embossed micro patterns were obtain d after co-firing. The embedded micro channels were also obtained by laminating the green tapes on the embossed substrates.