Researchers at Forschungszentrum Jülich have created a new type of transistor using a germanium-tin alloy, which offers several advantages over traditional switching components. The material allows charge carriers to move faster than in silicon or germanium, enabling lower voltage operation. This makes the transistor a promising option for future low-power, high-performance chips and quantum computer development.
Moore’s Law has held true for the past 70 years, with the number of transistors on a chip doubling every two years. However, the circuits have become so small that structures are now only 2-3 nanometers in size, reaching the limits of feasibility. As a result, researchers have been exploring alternatives to silicon, the primary semiconductor material, in search of materials with better electronic properties that can achieve the same performance with larger structures.
Germanium has been a focus of research, as electrons can move faster in germanium than in silicon. However, the team at Forschungszentrum Jülich went one step further and incorporated tin atoms into the germanium crystal lattice to further optimize electronic properties. The method was developed several years ago at the Peter Grünberg Institute (PGI-9) of Forschungszentrum Jülich.
The germanium-tin alloy tested by the researchers at Forschungszentrum Jülich offers a solution to overcome the physical limitations of silicon technology, according to Qing-Tai Zhao. The germanium-tin transistor has an electron mobility that is 2.5 times higher than a pure germanium transistor in experiments. The new material alloy is compatible with the existing CMOS process for chip fabrication, making it possible to integrate germanium-tin transistors directly into conventional silicon chips.
The potential of the germanium-tin transistor extends beyond classical digital computers to quantum computers. The transistor is expected to perform significantly better than silicon transistors at temperatures close to absolute zero, making it a promising material for quantum chips. Additionally, the germanium-tin transistor is a step towards optical on-chip data transmission, as it opens up the possibility of monolithic integration of nanoelectronics and photonics on a single chip.
The journal Communications Engineering has published the research paper. Dr. Dan Buca’s working group at Jülich has previously developed a germanium-tin laser, which further supports the potential of germanium-tin transistors in optically transmitting data on silicon chips.
Source: Forschungszentrum Juelich