“Silicon-based transistors often suffer from high switching loss during power transmission and fail when exposed to extremely high temperatures or levels of radiation,” said Jiangwei Liu. “Given the importance of developing devices that use less power and perform under harsh conditions, there has been a lot of interest within the broader scientific community in determining a way to build transistors that use manufactured diamonds, which are very durable.”
According to Professor Yasuo Koide, the lead researcher: “Manufactured diamonds have a number of physical properties that make them very interesting to researchers working with transistors. Not only are they physically hard, they also conduct heat well which means that they can cope with high levels of power and operate in hotter temperatures. In addition, they can endure larger voltages than existing semiconductor materials before breaking down.”
The research group has focused its work on enhancement-mode MOSFETs. The team deposited yttrium oxide directly onto the surface of the diamond to form a gate. According to Liu, yttrium oxide has many desirable qualities, including high thermal stability, strong affinity to oxygen and wide band gap energy.
“Ultimately, our team’s goal is to build integrated circuits with diamonds,” Prof Koide said. “We hope our work can support the development of energy-efficient devices that can function in conditions of extreme heat or radiation.”