Space science missions require detectors which are operating at temperatures of 170 K or even at lower temperatures (e.g. missions such as GAIA). For such type of science missions SiC based packages are often selected but the electrical routing is not included in their design.
Aluminium Nitride (AlN) or Aluminium Oxide (Al2O3) packages offer a very good performance for image sensors but one of their disadvantages is a high coefficient of thermal expansion (CTE). SiC as a package material is of great interest for science missions due to a very low CTE matching naturally the SiC structure of the focal plane array.
Main objective of this activity is focused on developing a complete SiC electronic packaging solution, integrating interconnection within the body of the package by using additive manufacturing.
Generally, SiC packages should be manufactured and tested in a proper way to meet the requirements for space. The aimed values of relative density (RD) and electrical resistivity are >95 % and >10^10 Ω cm. Another restriction is the requirement for a very low coefficient of thermal expansion. Targeted value is below 0.1 ppm K-1 at 73 K (value reported for commercial material).
First part of study was focusing on material selection in order to meet the requirements. More than 30 SiC based grades have been assessed and densified by pressure less sintering and hot-pressing and characterized with respect to the electrical resistivity. Only few grades came close to the requirements.
Second part of study was dealing with investigation of various additive manufacturing routes for preparation of SiC based packages using selected material grade and integration of conductive routing.
Techniques such as selective laser melting, lithography, binder jetting and indirect processes including fused filament printing and feedstock extrusion were studied and assessed. Each individual technique has its own pros and cons resulting in variations in processability, feasible resolution, electrical performance and overall package stability.
The present work focuses on main outcomes of densification of various SiC grades, impact of different additives on electrical performance and investigation of various additive manufacturing techniques for manufacturing of complex SiC based packages.

The activity is carried out under a programme of, and funded by, the European Space Agency. The view expressed in this article can in no way be taken to reflect the official opinion of the European Space Agency.