In 2011, the world held its breath when Japan’s Fukushima Daiichi nuclear power plant suffered a cooling system failure due to a magnitude 9.0 earthquake and tsunami. The concerns were not unfounded. The resulting meltdown, spreading highly radioactive material in multiple directions, made it one of the worst nuclear-related disasters in history.
Even after more than 10 years, cleaning is still ongoing. Last month, the Japanese government began testing procedures to remove radioactive debris from inside and around the plant. This is a critical step in the plant’s decommissioning process, which is expected to be completed by 2051.
Japanese groundbreaking startup Ookuma Diamond Device (ODD) is playing an interesting role in this process, with diamond chips used to remove radioactive debris via diamond chip drive amplifiers. And it has now raised 4 billion yen (about $27 million) to build the world’s first diamond semiconductor manufacturing facility in Ookuma, near Fukushima.
ODD plans to build the factory in January 2025 and operate it by the summer of 2026.
Why use diamond chips instead of traditional silicon-based semiconductors?
Diamond is known as a wide bandgap (WBG) semiconductor material; other materials include silicon carbide (SiC) and gallium nitride (GaN). WBG materials are considered to have better power conversion efficiency and superior thermal management.
Unlike silicon-based CPUs, GPUs, and NPUs, diamond-based chips have no circuit structure. Ken Nishimura, a partner at Coral Capital, told TechCrunch that diamond semiconductors act more like powerful control devices than small-scale power sources. He said diamond semiconductors will be used in large-scale facilities such as nuclear power plants that require extremely high temperatures and radiation levels that silicon-based chips cannot withstand.
A diamond semiconductor amplifier operating at 300°C was successfully prototyped using facilities at the Advanced Institute of Advanced Industrial Science and Technology (AIST) and Hokkaido University.
“The diamond semiconductors we develop are fundamentally different from traditional silicon-based chips due to their outstanding material properties,” Yuhei Nagai, CFO of Ookuma Diamond Device, said in an exclusive interview with TechCrunch. He added that compared with other advanced semiconductors such as SiC and GaN, diamond semiconductors provide excellent power conversion efficiency and improved thermal management functions for next-generation technologies such as 6G, space, defense, and nuclear.
It is also worth noting that diamond chips can be made from methane gas, making full production possible in Japan. This contrasts with GaN, which sources materials controlled by China.
ODD’s focus is on developing “pure diamond semiconductors” rather than GaN semiconductors on diamond substrates, Nagai said. According to a recent report, the market size for diamond materials used in chips is expected to grow from $113.7 million in 2023 to $10 billion in 2032.
The startup, a spin-off from Japan’s National Institute of Advanced Industrial Science and Technology (AIST) and Hokkaido University, was founded in 2021 specifically to help decommission the Fukushima Daiichi nuclear power plant.
The two co-founders, Dr. Junichi Kaneko and Dr. Hitoshi Umezawa, have been researching diamond chips for over 20 years. They said their work received attention after the disaster, which spurred more resources into R&D and the creation of startups. ODD builds the world’s first practical diamond chip in 2021.
The leap between theory, chip, and final product remains significant. The two co-founders are also leading a broader national project for the Japanese government to create a practical product that can remove radioactive debris from natural disasters.
“(ODD’s) prototype represents a world-first achievement. Until now, no one has been able to develop a working diamond semiconductor amplifier,” Nagai said.
A few global companies are also developing diamond semiconductors, including France’s Diamfab, Britain’s Element Six, and Japan’s ALMT, a subsidiary of Sumitomo Electric.
ODD differentiates itself by being the only company with end-to-end expertise, from substrate to packaging, to deliver world prototypes of diamond semiconductor amplifiers.
ODD is also talking to more than 10 potential customers around the world in the nuclear power plant, aerospace and telecommunications industries, Nagai said. Interest in the field grew this week after Google signed a deal to use nuclear power plants to power its data centers. strength.
Globis Capital partners led the latest round of funding, with participation from Coral Capital, aSTART, Green Co-Invest Investment, Japan Post Bank Spiral Regional Innovation Fund, and Mitsui Sumitomo, bringing total funding since inception to approximately $45 million (6.7 billion yen) I did it. Insurance Venture Capital, SMBC Venture Capital, etc.
The startup, which now employs 27 people, has received around $15 million in government grants from the Cabinet Office, METI, MIC, ATLA and the Reconstruction Agency.
