Advanced GaN Packaging - AGAPAC
Gallium Nitride (GaN) technology has recently made a remarkable breakthrough in the world of microwave electronics with the announcement of commercially available transistors from 5W to 180W at microwave frequencies. Originating from a major industrial transistor vendor in Japan but also from the US, equipment manufacturers and especially those related to space applications strongly believe that time has now come for a rapid insertion of GaN electronics into their systems. Apart from the reliability concerns that still need to be addressed and the present lack of a European source for GaN electronics, these GaN power transistors will roughly increase power density by more than an order of magnitude for large devices compared to present solutions (from 0.5 W/mm to 5 W/mm for space applications including de-ratings).
Consequences will directly impact packaging technology for which the thermal resistance needs to be significantly reduced if the advantages obtained at die level are to be maintained at its highest at the module and equipment level. To address this critical challenge for space satellite applications is the aim of the proposed project. This item is identified on the ESA roadmap [Ref:ESTEC/AC/418-20, ESA-IPC 2006] for GaN component strategy but is not funded by ESA. The ESA funding is being mainly dedicated toward GaN transistor process optimisation, reliability and industrialization and to build up a European GaN transistor device supply chain.
In this project, AGAPAC, which stands for “Advanced GaN Packaging”, the partners will endeavour to establish a space compatible European supply chain for packaging solutions of GaN HEMTs and GaN MMICs by 2010/11. To realize this project objective, the partners have defined sub-objectives that directly relate to 7 workpackages targeting:
This project will extend beyond state-of-the-art for high thermal dissipation composites (up to 600 W/mK) using materials based on diamond solutions as well as on carbon nano-fibres, compatible with hybrid micropackage manufacturing technologies. One challenge will be in developing a space compatible power micropackage able to withstand up to 100 W of dissipated power when standard same-size micropackages have a current maximum rating of around 25 W.
It has to be emphasized that the new micropackage developed here will be manufactured by a European manufacturer. Finally, a high power amplifier able to output up 150 W RF will be designed, manufactured and tested with GaN devices developed by a European foundry. We note the complementary nature of ESA funding (in particular also GREAT2) and FP7 Space funding.
The base for GaN power transistor technology is being developed within an ESA contract, while packaging is not.
The project officially started on the 1st October 2008 and will run for 3 years until the 30th September 2011.