GaN-on-Si Devices Show No Degradation from Irradiation

Imec reported that their 200mm gallium nitride-on-silicon (GaN-on-Si) e-mode power devices with a pGaN gate architecture demonstrated no degradation after receiving heavy ion and neutron irradiation. The irradiation tests were performed in collaboration with Thales Alenia Space, a maker of space systems. The results show that imec's 200mm GaN-on-Si platform offers GaN-based power devices can operate on earth as well in space applications.

GaN-on-silicon transistors can operate at higher temperatures, frequencies, and voltages, than their silicon counterparts. These performance capabilities make them perfect candidates for power conversion devices. Also, they show less power loss in electricity conversion.

Imec irradiated its latest generation of 200mm GaN-on-Si e-mode pGaN devices with neutrons and heavy ions (Xenon). Pre and post-irradiation tests revealed no permanent degradation of transistor characteristics including no threshold voltage shifts nor gate rupture. The excellent radiation hardness of imec’s devices enables space applications where fluxes of heavy ions and neutrons can damage electronic circuits in space stations and satellites.

Thales Alenia Space Belgium found that the result obtained with Imec’s GaN-on-Si devices is an important milestone towards the development of space-based power conversion applications.

Rudi Cartuyvels, Executive Vice President at imec, commented, “At imec, we use 200mm silicon substrates for GaN epitaxy and this technology can be used on 200mm 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.”

These results were achieved during the first phase of the European Space Agency (ESA) project “ESA AO/1-7688/13/NL/RA”, GaN devices for space-based DC-DC power conversion applications. The results show that the p-GaN devices offer excellent radiation robustness for operation in space. For the second phase of the project, imec intends to industrialize this technology for a future space qualification program.