⚡ Over 10% of the world's electricity vanishes as heat during power conversion.
A breakthrough material called "gallium oxide" could change everything. FLOSFIA, a Kyoto University spinoff, has just achieved mass production technology for 4-inch wafers—at just 1/50th the cost of competing SiC substrates.
With manufacturing equipment costs also slashed to 1/10th, this Japanese-origin technology is positioning to disrupt the global semiconductor landscape.
What Is Gallium Oxide? The "Ultimate Material" for Power Semiconductors
Power semiconductors are essential components that convert and control electrical power. While silicon (Si) has dominated for decades, next-generation materials like silicon carbide (SiC) and gallium nitride (GaN) are gaining traction.
But gallium oxide (Ga2O3) stands apart. The "Baliga figure of merit"—a key indicator of power semiconductor performance—tells the story clearly. If silicon equals 1, SiC scores around 500, and GaN reaches approximately 930. Gallium oxide? Between 3,444 and 6,726, depending on crystal structure.
This means gallium oxide could theoretically achieve far more efficient power conversion than any currently available material.
FLOSFIA's Technical Breakthrough
In December 2025, Kyoto University startup FLOSFIA announced a significant milestone.
The company completed verification of manufacturing technology for 4-inch gallium oxide (α-Ga2O3) wafers for power semiconductor devices. Additionally, prototype Schottky barrier diodes (SBDs) demonstrated substantially improved reliability.
Key achievements include:
- 600V breakdown voltage, 10A-class devices successfully prototyped
- Leakage current under reverse voltage reduced to less than 1/1000th of previous levels
- Devices survived 1,500 hours of continuous reverse bias testing at 150°C
Three Reasons for the Dramatic Cost Advantage
FLOSFIA's gallium oxide technology attracts attention primarily for its overwhelming cost competitiveness.
1. Sapphire Substrate Utilization
Approximately 48% of SiC device manufacturing costs come from substrates. FLOSFIA's α-Ga2O3 devices use widely available, inexpensive sapphire substrates—reducing substrate costs by up to 50 times.
2. Proprietary "Mist Dry Method"
FLOSFIA developed "Mist Dry," an evolution of Kyoto University's "Mist CVD" technology. Raw materials are atomized and deposited onto heated substrates at temperatures below 500°C. Since SiC manufacturing requires 1,500-2,000°C, this approach cuts equipment investment to less than 1/10th.
3. Existing Factory Compatibility
The technology can utilize process equipment already installed in GaN-LED and SiC factories, significantly lowering barriers to mass production.
Applications and Market Outlook
Gallium oxide power semiconductors have diverse applications: EV power control units, data center power supplies, solar inverters, and industrial robot drive systems.
The EV market particularly benefits from gallium oxide's low power loss characteristics, potentially extending range and reducing charging times.
According to Yano Research Institute, the global wide-bandgap semiconductor crystal market is projected to reach 286.9 billion yen in 2025 and 829.8 billion yen by 2035. The overall next-generation power semiconductor market is expected to grow at approximately 20% annually, reaching around 3.5 trillion yen by 2035.
Implications for Japan's Semiconductor Industry
The SiC market currently faces intense price competition due to slowing EV demand and massive investment by Chinese manufacturers. Japanese companies maintain technological advantages but struggle with cost competitiveness.
FLOSFIA's α-Ga2O3 technology offers a potential breakthrough. The company has filed over 700 patents, creating significant barriers to entry through its "only-one technology" approach.
Major Japanese corporations have invested in FLOSFIA, including DENSO, Mitsubishi Heavy Industries, Daikin Industries, Yaskawa Electric, and JSR. The company raised a cumulative 14.5 billion yen through Series E funding, achieving a valuation of 145 billion yen.
Future Prospects and Challenges
FLOSFIA plans to expand its lineup from 600V to 1,200V and 1,700V breakdown voltages, with current ratings increasing from 10A to hundreds of amperes.
Challenges remain. Gallium oxide historically struggled with P-type semiconductor layer formation—but FLOSFIA developed the world's first P-type material, iridium-gallium oxide (α-(IrGa)2O3), overcoming this barrier. Sample shipments of next-generation JBS-structure SBDs are scheduled to begin in 2025.
As the world pursues carbon neutrality, improving energy efficiency is a universal priority. Whether Japanese gallium oxide technology becomes a key solution to this challenge has captured global attention.
Japan is increasingly focused on gallium oxide as the "post-SiC" material. What's happening with next-generation power semiconductor development in your country? Share your thoughts in the comments!
References
Reactions in Japan
FLOSFIA's 4-inch wafer mass production technology is finally here. The cost at 1/50th of SiC is shocking. I sense the potential for Japanese technology to change the world. Definitely worth watching as an investment.
The Baliga figure of merit for gallium oxide being over 10 times that of SiC is a dream number theoretically. But actual product performance is another story. I'll watch with tempered expectations.
It's emotional to see a Kyoto University startup come this far. With DENSO and Daikin investing, you can sense their seriousness. I hope this becomes a beacon of hope for Japan's semiconductor revival.
Even if costs are 1/50th, mass production hasn't actually started yet. SiC also sounded like a dream initially but took over 10 years to spread. We shouldn't get too excited.
If power conversion efficiency improves, solar power system efficiency will improve too. This kind of foundational technology advancement is truly important for achieving carbon neutrality. Cheering them on!
Achieving a low-temperature process below 500°C with the Mist Dry method is technically significant. The P-type semiconductor challenge is also being addressed with iridium-gallium oxide. Steady progress is being made.
With China aggressively attacking prices in the SiC market, Japan competing with a different material might be a smart strategy. But China is also advancing gallium oxide research, so we can't let our guard down.
A valuation of 145 billion yen and 14.5 billion yen raised in Series E. It's truly amazing for a Japanese deep-tech startup to achieve this. I hope they become a role model.
Leakage current reduced to 1/1000th and passing 1500-hour reliability tests at 150°C are impressive numbers. But even stricter tests await for automotive grade certification. The road is still long.
Technology from Professor Fujita's lab is finally blossoming. I've been watching since they developed Mist CVD, but I never imagined they'd come this far. They've proven the potential of university spinoffs.
Japan's semiconductor industry is at a crossroads to avoid a 'second defeat.' Gallium oxide is one of the few areas where we can compete purely on technology. We should support it fully, including government backing.
Data center power consumption is a serious problem, worsening with AI proliferation. If power conversion efficiency improves, cooling costs will drop too. I hope gallium oxide gets commercialized soon.
The interesting thing about gallium oxide is how α-type and β-type differ. FLOSFIA does α-type, Novel Crystal does β-type—Japanese companies lead globally in both. This field is Japan's domain.
The technology is probably amazing, but capturing the market is a different issue. Japan led in SiC and GaN too, but overseas competitors took over. I hope we don't repeat the same mistakes.
If it extends range and shortens charging time, I'm all for it. Tesla and BYD are sensitive to new tech, so I'd love to see Japanese gallium oxide devices in EVs worldwide.
I'm a semiconductor engineer in the US. I've been following gallium oxide research, but I didn't know Japan had advanced mass production technology this far. The cost advantage is intriguing. This is technology we should pay attention to.
I work at a German automaker. We're struggling with SiC supply chain issues, so I'm very interested in alternative materials. I'd like to contact Japan's FLOSFIA.
I research gallium oxide at a Chinese research institute. FLOSFIA's patent portfolio is very strong, and catching up to their α-type technology won't be easy. I have to admit it's excellent technology.
I work at an investment fund in London. It's impressive that a Japanese deep-tech startup achieved this scale of funding. If they have plans for global expansion, we'd consider investing.
I'm a tech blogger from India. I'm interested in how this technology will be used in renewable energy. India is also promoting solar power, so efficiency improvements are very welcome.
I work at an EV startup in Sweden. Supply chain diversification is a key challenge. Japan's gallium oxide technology could be an option to reduce dependence on China.
I operate data centers in the US. Power costs are one of our biggest challenges. If power conversion efficiency improves dramatically, I'm eagerly awaiting commercialization of this technology.
I work at a French energy company. On the road to carbon neutrality, efficiency improvement technologies like this are essential. I hope adoption will progress in Europe as well.
I'm a semiconductor engineer in Korea. Honestly, I'm surprised by Japan's progress in gallium oxide technology. Korea needs to accelerate research too. Healthy competition advances technology.
I work at a solar company in the UAE. There's high demand for efficient power devices that work in harsh desert conditions. We'd like to consider collaboration with Japanese companies.
I'm a veteran engineer in Silicon Valley. I've seen many 'revolutionary' announcements about new materials, but there are many barriers to actual market entry. I'll judge after seeing actual results.
I work at a renewable energy company in Brazil. It would be wonderful if this technology becomes available in the South American market. Cost reduction is key to opening up emerging markets.
I work at a semiconductor company in Taiwan. TSMC is also watching the power semiconductor market. Japan's gallium oxide technology has the potential to energize the entire market.
I work at an EV charging infrastructure company in Australia. Improving charging efficiency is very important for our business. We'll be closely watching developments in this technology.
I work at a Swiss industrial equipment manufacturer. High-efficiency power supplies are essential for precision equipment. I've always trusted Japanese technology, and I have high expectations for this new material.