A team of researchers from ETH Zurich, a leading university in Switzerland, has used a specialized beamline at ANSTO’s Centre for Accelerator Science (CAS) to study the effects of high energy irradiation on silicon carbide, a new semiconductor material for power electronics. The researchers hope to improve the performance and reliability of silicon carbide devices, which have applications in electric vehicles, renewable energy, and smart grids.
Silicon carbide (SiC) is a promising material for power electronics, as it has several advantages over the conventional silicon-based devices, such as higher efficiency, lower losses, higher temperature tolerance, and higher voltage capability. However, SiC devices also face some challenges, such as defects, degradation, and instability, caused by the exposure to radiation and high electric fields.
To understand and overcome these challenges, the researchers from ETH Zurich, led by Professor Ulrike Grossner, have been developing and characterizing SiC devices for several years. They have also been collaborating with other institutions and industry partners, such as the European Space Agency (ESA) and ABB, a global technology company.
One of their main goals is to investigate the radiation effects on SiC devices, which are relevant for space and nuclear applications, as well as for terrestrial applications that involve high radiation environments, such as medical equipment, security systems, and particle accelerators.
The experiment and the results of the research
To conduct their experiment, the researchers visited ANSTO’s CAS in January 2024, where they used the Sirius accelerator, a state-of-the-art facility that can generate high energy beams of protons and heavier ions. The Sirius accelerator is optimized for radiation testing of electronic components, power devices, and photovoltaic technologies, and offers a high degree of flexibility and precision.
The researchers brought several samples of SiC devices, such as diodes and transistors, and irradiated them with different types and doses of ions, ranging from protons to xenon. They also measured the electrical characteristics of the devices before and after the irradiation, using a custom-made setup that they designed and built.
The researchers were able to observe and analyze the changes in the devices caused by the irradiation, such as the increase in the leakage current, the decrease in the breakdown voltage, and the formation of defects and traps. They were also able to compare the effects of different ions and energies, and to identify the mechanisms and the factors that influence the radiation response of SiC devices.
The researchers were assisted by ANSTO’s accelerator scientists, Dr Stefania Peracchi, Dr Zeljko Pastuovic, and Dr Ryan Drury, who have expertise in accelerator technologies and radiation effects. The ANSTO team also helped the researchers to prepare and align their samples, to operate and control the beamline, and to collect and process the data.
The significance and the impact of the research
The research is significant for advancing the knowledge and the technology of SiC devices, which have potential applications in various fields and sectors that require high performance and reliability of power electronics. The research is also important for establishing and strengthening the collaboration between ETH Zurich and ANSTO, as well as other partners and stakeholders in the field.
The research is expected to have a positive impact on the development and the optimization of SiC devices, as well as on the design and the selection of the best materials and devices for different applications and environments. The research is also expected to contribute to the innovation and the competitiveness of the power electronics industry, as well as to the sustainability and the security of the energy systems.