Latest / The Manufacturing Podcast with Fexingo: Factories, Supply Chains, and Industrial Business / How a German Factory Is Growing Diamonds in a Lab
Transcript
- Lucas: So there is a factory in Augsburg, Germany, that grows diamonds. Not mining, not digging, not conflict zones — they grow them in a chamber about the size of a washing machine, using methane gas and microwave energy. Luna: Wait — like, jewelry diamonds? Engagement ring diamonds? Lucas: Those too, sure, but the real action is industrial. This facility produces diamonds for semiconductor heat sinks, quantum computing components, and surgical scalpel blades. The process is called chemical vapor deposition — CVD — and it is one of the most precise manufacturing operations I have ever looked into. Luna: Okay, walk me through it. How do you 'grow' a diamond in a machine? Lucas: You start with a thin slice of diamond — a seed crystal — placed on a substrate inside a vacuum chamber. You pump in hydrogen and methane gas, heat the chamber to about 800 degrees Celsius, and then hit it with microwaves. That creates a plasma ball that breaks the gas molecules apart. Carbon atoms rain down onto the seed and crystallize into diamond, layer by layer, at about one micron per hour. Luna: So it is essentially a very hot, very controlled carbon rainstorm. How long does it take to get a wearable stone? Lucas: A one-carat rough diamond takes about two weeks. That is two weeks from methane gas to a gem-quality stone that is chemically and optically identical to a mined diamond. The factory in Augsburg has about thirty reactors running simultaneously, so they can produce thousands of carats per month. Luna: Let me guess: the energy bill is enormous. Lucas: It is significant, yes. Each reactor draws about 10 kilowatts, so thirty reactors running 24/7 is about 7,200 kilowatt-hours per day. But the company has paired the factory with a local solar farm and a biogas plant, so they claim carbon-neutral production. That is a big selling point — especially for luxury brands that are trying to clean up their supply chain. Luna: Right, because mined diamonds have that whole carbon footprint plus the ethical baggage. But I remember reading that lab-grown diamonds crashed the price of small stones. What is the economics here? Lucas: Let me give you the numbers. A decade ago, a one-carat lab-grown diamond cost about $4,000 to produce. Today, the same stone costs around $300. Mined diamonds of comparable quality still retail for $4,000 to $6,000 for a one-carat natural. So the margin for lab-grown is decent, but the real profit is in industrial applications where you need specific properties. Luna: Such as? Lucas: Diamond is the best thermal conductor known. It conducts heat five times better than copper. So for high-power electronics — think 5G base stations, laser diodes, electric vehicle inverters — you can use a diamond heat sink to pull heat away from chips. That lets you run the chip harder without melting it. The Augsburg factory ships industrial-grade diamond wafers to a semiconductor equipment maker in the Netherlands. Luna: So we are past the lab-grown diamond being a novelty. It is a legitimate industrial material now. Lucas: Absolutely. And there is a whole second application in quantum computing. Certain defects in diamond — nitrogen-vacancy centers — can act as qubits. They are stable at room temperature, which is rare for quantum systems. So there is a startup in Munich that buys these diamonds and uses them to build quantum sensors. They are a long way from a commercial quantum computer, but the sensor business is real. Luna: I want to go back to the surgical tools. Diamond scalpels? Lucas: Yes. Diamond blades are extraordinarily sharp and stay sharp far longer than steel. For eye surgery — cataract incisions, corneal transplants — a diamond knife gives a cleaner cut, less tissue damage, faster healing. The Augsburg factory grows diamond wafers, then lasers them into blades that are sold to medical device companies. A single blade can cost $500, but it lasts for hundreds of procedures. Luna: That is a pretty niche supply chain. Are there any other factories doing this, or is Augsburg unique? Lucas: There are about a dozen major CVD diamond producers worldwide — one in Singapore, one in the UK, a couple in China. But most of them focus on gemstones for jewelry. The Augsburg factory is unusual because roughly 70 percent of their output goes to industrial and medical customers. They do not even brand their diamonds for retail. They sell B2B. Luna: That is smart — avoid the consumer price war and capture the high-margin technical applications. What is the biggest challenge they face right now? Lucas: Scaling the reactors. The current generation can produce wafers up to about four inches in diameter. For semiconductor applications, the industry wants six-inch or even eight-inch wafers. Growing a larger diamond without defects is hard. The company is working on a new reactor design that should hit six inches by early 2027. If they pull that off, they could become a key supplier to the chip industry. Luna: And that would be a big deal because the chip industry is desperate for better thermal management as transistors get denser. Lucas: Exactly. And you know, it is interesting — we talk about reshoring and supply chain resilience a lot on this show. Here is a case where Germany is not just making a commodity cheaper. They are making a material that was once scarce and environmentally damaging, and they are making it cleaner, more available, and with better properties. That is manufacturing innovation in a nutshell. Luna: I want to ask about something related. This kind of deep-tech manufacturing — it is expensive to set up, expensive to run. How do these companies fund the growth? Lucas: The Augsburg factory was backed by a mix of venture capital and German government grants for climate-friendly industrial processes. They raised about 50 million euros over three rounds. The unit economics work because the industrial customers sign long-term supply agreements. Once a medical device company qualifies your diamond blade, they are not going to switch suppliers easily. Luna: That is a moat. Lucas: That is a real moat. And it is the kind of story we try to cover — a specific factory, a specific process, a specific number. You could go visit this plant, stand next to the reactor, and see a diamond growing at one micron per hour. Luna: So if someone is listening and thinking about how to apply this to their own work — maybe not diamond growing, but a similar precision manufacturing challenge — what is the takeaway? Lucas: I think it is that the boundaries between materials science, clean energy, and manufacturing are blurring. This factory is not just a factory. It is a lab that happens to produce at scale. And that is increasingly what competitive manufacturing looks like. Luna: Yeah, I think that is right. And these conversations — if they have moved your work forward in some small way, that is exactly why we do it. We deliberately do not run ads on these. If you want to support that choice, the link is buy me a coffee dot com slash fexingo. Lucas: And we really mean that. No pressure, just if the show is useful to you. Okay, back to the Augsburg plant — I mentioned they plan to double capacity by 2027. That means building a second building, adding thirty more reactors, and hiring about fifty new engineers and technicians. The local government is supporting them with a fast-track permitting process. Luna: Because they want to attract more deep-tech manufacturing to the region. Lucas: Exactly. And that is a pattern we see across Europe — regions competing to host these advanced factories. Augsburg is not traditionally a tech hub, but they have cheap industrial land, a decent engineering university, and a supportive mayor. It is a reminder that manufacturing clusters can emerge anywhere if the conditions are right. Luna: I am curious about the labor side. How do you find people who can operate a plasma reactor growing diamonds? Lucas: That is a real bottleneck. The factory runs three shifts, and each shift needs at least two technicians who understand vacuum systems, gas handling, and crystal growth. They have partnered with a local technical college to create a two-year certification program. The first cohort graduated last year, and all ten were hired immediately. Luna: So they are essentially building their own labor pipeline. Lucas: Yes. And that is something we see in a lot of successful factories — they do not just wait for the labor market to provide talent. They invest in training. It costs them about 20,000 euros per student, but they get a technician who stays for years. Luna: That is a good return if retention is high. Lucas: Retention is over 90 percent in the first three years, which is excellent for manufacturing. People like working with cutting-edge technology. It is not a dead-end job. Luna: Alright, last question: what is the coolest application you saw that we have not mentioned? Lucas: There is a project with a German university where they are using CVD diamond to make particle detectors for fusion reactors. Diamond is radiation-hard — it does not degrade in the intense neutron flux inside a fusion plasma. So they are growing custom diamond sensors that can measure temperatures and magnetic fields inside a working fusion experiment. That is wild to me. Luna: Diamond sensors in a fusion reactor. That is like something out of science fiction. Lucas: It is, but it is real. And it is being manufactured in a factory in Augsburg that did not exist five years ago. That is the pace of change in industrial manufacturing. Luna: Well, I think we have a solid angle for a follow-up when they hit the six-inch wafer milestone. Lucas: Agreed. We will keep an eye on it.