HEATPACK project aims to develop and validate critical technology building blocks for enabling transformative packages for space applications with very low thermal resistance. This is to fully exploit the potential of wide-bandgap technologies which are now being considered as critical in numerous sectors and for space applications in particular, as enhanced thermal management solutions beyond state-of-the-art need to be provided. Benefits will range from improved performance to increased components reliability and lifetime. HEATPACK concepts for achieving high power / high thermal efficiency packages include: - Diamond based composite materials with a thermal conductivity >600W/m.K to be used as baseplate or insert - Silver sintering based Thermal Interface Material (TIM) for components assembly - TIM for package to structure assembly with both electrical and thermal enhanced properties (in excess of 10W/m.K) - Innovative cooling solutions with strategic implementation possibilities (baseplate, lid, structure…). Using these technologies, two different modules implementing Gallium Nitride (GaN) components will be developed: -A power supply switching module based on a multilayer ceramic substrate -A Ka-band High Power Amplifier based on a surface mount hermetic micro package. The main applications targeted are satellite’s output power section for telecommunication missions in particular, as well as power conditioning / power supply units concerning all satellite payload’s equipment consisting of high power supplies. To secure a fully European supply chain for high power components thermal management, the technologies developed will reach a TRL of 6, demonstrating commercial viable solutions providing reliability levels compliant with space environments.