by Helen Duncan, Managing Director, MWE Media
The United States is without doubt the epicentre of the gallium nitride (GaN) RF industry, being home to the two biggest players, Wolfspeed and Qorvo. However it would be a mistake to think that they have no competition from “across the pond,” or further afield. While in Asia-Pacific WIN Semiconductors provides a GaN pure-play foundry service in Taiwan, there is in fact also a thriving GaN supply chain within Europe, with several ongoing national and EU initiatives aimed at stimulating it further.
So who’s who in European GaN, and who is making the running? It’s no secret among the European microwave community that France is ahead in the game as far as GaN fabs are concerned, with OMMIC and UMS each offering both foundry and standard product ranges.
Previously focused on GaN-on-SiC for the space market, OMMIC has recently launched a new 100nm gate length GaN-on-Si process for both RF power and low noise, aimed at 5G base station and automotive applications, and has announced plans to eventually increase capacity to more than 2 million chips per year to address these volume markets.
United Monolithic Semiconductors (UMS) has a site in Villebon, France and a German site in Ulm. A joint venture between Thales and Airbus, it develops and manufactures RF and mmWave MMICs, including many in GaN, for telecoms, automotive, defense and space applications, as well as offering a foundry service.
French-Italian joint venture STMicroelectronics is another leading player in GaN MMICs, although in GaN-on-Si rather than on SiC. Through its collaboration with MACOM, STMicroelectronics is targeting global 5G base station applications by expanding production capacity of 150mm GaN-on-Si and further scaling up to 200mm wafers, with plans announced to extend this also to handset applications.
NXP has facilities in both The Netherlands and France, and manufactures RF PA ICs in GaN as well as LDMOS, for base station applications. Its spinoff Ampleon specialises in power devices for microwave heating.
The UK, where the very first MMIC was developed in the 1970s, had until recently fallen behind in compound semiconductor fab capability due to industry consolidation. However it is home to world-class GaN-on-SiC epitaxy capability from IQE plc, based in Cardiff, Wales, and also to some very experienced fabless MMIC design teams, including those at Plextek RFI and Viper RF. A number of developers of components and subsystems based around GaN also have operations in the UK.
Recent years have seen renewed growth, however. The INEX RF GaN facility in Newcastle, UK, has been developed over the past four years to provide local manufacture of RF GaN devices for the defense market. Both 0.5µm and 0.25µm GaN-on-SiC technologies have been demonstrated, with the intention of moving towards 0.15µm.
Overall, the UK supply chain in GaN is being primed by a cluster of inter-related institutions that have been set up around Cardiff, with support from Innovate UK (a government agency). CS Connected is the fifth semiconductor cluster in Europe, and the first devoted to compound semiconductors. It began in 2014 with the Innovation Campus at Cardiff University, then both the Compound Semiconductor Institute and the Compound Semiconductor Centre (a joint spin-off with IQE) were established. In 2016 the Compound Semiconductor Applications (CSA) Catapult followed, along with the EPSRC CS Manufacturing Hub, which seeks to strengthen the transfer of designs into manufacturing. This all may sound rather confusing, but the message is clear: the UK is now making its mark in GaN, as it once did in GaAs.