Imec, a leading research and innovation hub in nano-electronics and digital technologies, announced that 200 mm GaN on Si e-mode power devices with a pGaN gate architecture showed no degradation after heavy ion and neutron irradiation. The testing was performed in collaboration with Thales Alenia Space. The results demonstrate that imec’s 200 mm GaN on Si platform supports GaN power devices for space applications.

Imec’s latest generation of  200 mm GaN-on-Si e-mode pGaN devices were irradiated with heavy ions (Xenon) and neutrons. Pre and post irradiation tests revealed that there was no permanent degradation of transistor characteristics: no shifts in threshold voltage nor gate rupture. The excellent radiation hardness of imec’s devices is important, as it enables applications in space, where fluxes of heavy ions and neutrons can damage electronic circuits in satellites and space stations. These results were achieved as part of the European Space Agency (ESA) project “ESA AO/1-7688/13/NL/RA,” GaN devices for space based DC-DC power conversion applications.

GaN on Si transistors operate at higher voltages, frequencies and temperatures than their silicon counterparts. This makes them candidates for power conversion devices, as they show lower power losses in electricity conversion. First-generation GaN-based power devices are used today and will play a key role in the power conversion of future electronic devices, such as battery chargers, smartphones, computers, servers, automotive, lighting systems and photovoltaics.

Imec is developing the next-generation of GaN-based power devices with improved performance and reliability. Imec’s latest 200 mm GaN-on-Si platform shows good wafer-to-wafer reproducibility and low dynamic Rdson. The platform is currently available for dedicated development or technology transfer to imec partners.

For many years, Thales Alenia Space Belgium has surveyed the evolution in the wide band-gap devices. These components are promising for their significant increase in performances. However, robustness to space radiation is mandatory for electronic devices in our space equipment. The result obtained with Imec’s GaN-on-Si devices is an important step in the way to space based power conversion applications.

“These results are important to start using this promising technology for space applications. Also, it demonstrates that our 200 mm GaN on Si platform has reached a high level of technology readiness and can be adopted by industry,” stated Rudi Cartuyvels, executive vice president at imec. “At imec, we use 200 mm silicon substrates for GaN epitaxy and this technology can be used on 200 mm CMOS-compatible infrastructure. Thanks to innovations in transistor architecture and substrate technology, we’ve succeeded in making GaN devices on larger wafer diameters than used today, which brings lower cost perspectives for the second generation of GaN on Si power devices. Imec is also looking beyond today’s technology, exploring novel substrates, higher level of integrations and novel devices.”

Andrew Barnes, the ESA technical officer overseeing the project, stated, “GaN is a critical technology for future space missions with a wide range of potential applications, including smaller size, higher efficiency DC-DC power conversion subsystems. These results, obtained from the first phase of an ESA GSTP project, are important and show that the p-GaN devices developed by imec offer excellent radiation robustness for operation in space. In the second phase of the project it is planned to industrialize this technology in readiness for a future space qualification program.”