In March, the Kassiopeia project was launched to provide a value-added chain using internationally leading technology only available in Europe. The consortium project, led by Ferdinand-Braun-Institut (FBH) in Berlin, aims to demonstrate a fully independent European supply chain, from silicon carbide (SiC) substrates, gallium nitride (GaN) epitaxy, GaN device processing up to power amplifiers. For this purpose, Ka-band MMICs using novel epitaxy, processing, and circuit concepts towards highly efficient GaN and aluminium nitride (AlN) devices will be developed and demonstrated. The Ka-band frequency band is used, for example, in satellite communications.
FBH contributes its industry-compatible Ka-band MMIC technology on 100 mm GaN-on-SiC wafers. “Unique selling point of our GaN MMIC technology is its highly reproducible and reliable iridium sputter-gate technology”, emphasizes Dr. Joachim Würfl, head of FBH’s Power Electronics Department. “This technique reduces dynamic losses (gate lagging) to values up to two times less than competing institutional and industrial technologies.” The technology is also known to significantly improve device reliability. Together with new approaches in terms of process technology and circuit concepts both targeting for parasitic loss reduction highly efficient Ka-band MMICs will be developed. The groundbreaking technology will thus provide advantages in performance and reliability, which are particularly important for spaceborne devices.
SweGaN participates with its unique buffer-free solution for GaN-on-SiC epiwafers, QuanFINE®, bringing its expertise in epitaxial layer design and optimization to the project. SweGaN will also supply in-house developed semi-insulating SiC substrates for evaluation. These activities are financially supported by the Swedish National Space Agency (Rymdstyrelsen). SweGaN is recognized for providing GaN epitaxial wafers for sub-6 GHz and mm-wave transistors with a significantly low thermal boundary resistance and limited trapping effects – based on its proprietary buffer-free approach. The epiwafer specialist supplies epitaxial material to leading manufacturers of components and devices for satellite communications, telecom, and defense applications, plus power electronics for electric vehicles, solar inverters and more. "We are excited to participate in this ESA-aligned project together with FBH and University of Bristol, shares Jr-Tai Chen, CTO, SweGaN. Conventional GaN-on-SiC materials for Ka band applications still lack maturity, leaving significant room for innovation and improvement. SweGaN will introduce its revolutionary epitaxial manufacturing process to address the challenge.”
The University of Bristol’s research within this program focuses on direct thermal measurements on active GaN transistors by using micro-Raman thermography and advanced device characterizations and modeling. This will provide a continuous feed-back to all device and epitaxial developments planned in Kassiopeia.
The Kassiopeia project is funded under the ESA ARTES Advanced Technology Programme: “European Ka-band high power solid-state technology for active antennas”.