Germanium, or Ge on the periodic table, is a scarce and fascinating metal that some of the world’s most advanced and demanding technologies cannot do without. Experts from Umicore’s Electro-Optic Materials (EOM) Business Unit -- Geert Vandenhoeck, Director Strategic Development & Sourcing, and Bendix De Meulemeester, Director of Marketing and Business Development -- share their passion for the powers of this critical metal and explain how Umicore’s closed-loop recycling technology is key to ensuring a sustainable supply of germanium in Europe.
Ge at a glance
Germanium is a critical raw material that keeps the world connected, powering advanced electronic and optical applications. It is refined by Umicore into one of the planet’s purest materials, achieving purity levels up to 99.99999999999%.
Umicore’s germanium story began in the 1950s, when the metal appeared as an impurity that needed to be removed during zinc processing. Around the same time, the very first applications of germanium emerged in early transistors, and soon after Umicore started refining germanium for specific uses.
Since those early days, Umicore has developed one of the world’s most advanced and integrated germanium processing facilities, handling every step from extracting small quantities from waste materials and refining these into ultra-pure crystals and substrates. Our closed loop business model enables us to be a resilient global supplier of germanium products.
Umicore’s advanced pyrometallurgical and hydrometallurgical refining processes enable it to process a wide range of Ge feedstocks, including those with as little as 0.5% germanium content. “Our sourcing of germanium has been 100% sustainable since 2022 – we only source primary germanium from zinc mining sources to supplement our recycling activities, which now account for over 50% of the germanium we process. Beyond this, we are continuously looking for ways to use germanium more efficiently,” says Bendix.
From telecommunications to Mars missions
Today, germanium is at the frontier of next-generation innovations. “Germanium is the salt and pepper of society — we need small quantities of it to power many technologies. You can’t see it, yet it’s impossible to do without,” says Bendix.
It enables breakthroughs in semiconductors and silicon photonics-based telecommunications, such as 5G Wi-Fi connections and ultra-fast data transfer for energy-intensive AI data centres, among other more traditional applications like LEDs and lasers.
Germanium’s optical applications have made it indispensable for infrared imaging, from security systems to thermal cameras used in firefighting. During the Covid-19 pandemic, temperature screening relied on these technologies.
Beyond Earth, germanium plays a vital role in space exploration. Its durability and radiation resistance make it essential for high-efficiency solar cells powering satellites and even Mars missions. “As the space market is set to grow tenfold over the next decade, the demand for high-efficiency solar cells is soaring — yet traditional solar cells aren’t built to last forever. At Umicore, we’re pioneering germanium-based technologies for satellite solar cells that drastically reduce Ge material use,” says Geert.
Doing more with less
Umicore is gradually substituting germanium in optics through proprietary material innovations such as GASIR® chalcogenide glass and Tessella™ wafer moulding, which make infrared lenses lighter, more affordable, and scalable for mass markets. “These advances are paving the way for integration in the future of automotive safety, where thermal cameras detect pedestrians and obstacles in the dark. Umicore’s GASIR® chalcogenide glass, which uses 80% less germanium makes this high-volume application possible,” Bendix says.
Earlier this year, Umicore entered into two strategic EU-backed germanium projects under the Critical Raw Materials (CRM) Act. These initiatives focus on process innovation to boost recovery yields from complex waste streams and new manufacturing methods that drastically reduce germanium consumption in satellite solar-cell substrates.
“As one of the most important germanium refiners outside China, Umicore’s expertise is vital for strengthening global supply chain resilience, improving resource efficiency, and ensuring sustainable access to this critical material for high-tech industries,” says Geert.
Unique metal, unique Business Unit
The Electro-Optic Materials Business Unit at Umicore is unique in that it manages the entire germanium value chain, from upstream sourcing, refining and recycling to added value downstream products. This differs from the way we process other metals at Umicore across multiple business units. This structure enables germanium closed-loop coordination, operational efficiency, and the ability to serve diverse customer markets such as satellites, fibre optics, and thermal imaging from one specialised team.
Looking to the future, ultrapure germanium crystals are currently used to build giant instruments to detect dark matter in our universe, giving the metal an otherworldly significance.
Umicore is responsible for pioneering one of the world’s purest germanium crystals. As one of the only companies on the planet that can endlessly refine and recycle Ge at this level, we have a responsibility toward society to keep providing this technology. It’s an awe-inspiring metal that may hold answers to some of the universe’s deepest mysteries.
