Researchers at Forschungszentrum Jülich and the Leibniz Institute for Innovative Microelectronics (IHP) have developed a material that did not exist before: a stable alloy of carbon, silicon, germanium, and tin. The new compound opens up new possibilities for applications at the intersection of electronics, photonics, and quantum technology.
www.all-about-industries.com/, Jul. 18, 2025 –
The four elements of the new compound CSiGeSn, like silicon, originate from the fourth group of the periodic table. This makes the alloy compatible with the standard process of the chip industry, the so-called CMOS process—a decisive advantage.
"With the combination of these four elements, we have achieved a long-pursued goal: the ultimate semiconductor based on the fourth group," explains Dr. Dan Buca from the Jülich Research Center.
The new alloy allows properties to be finely tuned, enabling components that would not be achievable with pure silicon: for example, for optical components or quantum circuits. The structures can be created directly on the chip during manufacturing.
Chemistry sets clear limits here: only elements belonging to the same group as silicon seamlessly integrate into the crystal lattice on the wafer. Elements from other groups disrupt the delicate structure.
The underlying process is called epitaxy, a key process in semiconductor technology, where thin layers are deposited atomically on a substrate.
Previously, Dan Buca and his team had successfully combined silicon, germanium, and tin to develop transistors, photodetectors, lasers, LEDs, and thermoelectric materials.
The addition of carbon now expands the possibilities for precisely tuning the bandgap—a key factor for electronic and photonic behavior.
"An example is a laser that works at room temperature. Many optical applications from the silicon group are still in their infancy," explains Dan Buca.
"New possibilities also arise for the development of suitable thermoelectrics to convert heat from wearables and computer chips into electrical energy."