Scientists, both domestic and international, have developed the world's first functional semiconductor using graphene, with the electron mobility of the graphene semiconductor being 10 times that of silicon. This new type of semiconductor can be used to manufacture smaller and faster electronic devices or for quantum computing.
Scientists, both domestic and international, have developed the world’s first functional semiconductor using graphene, with the electron mobility of the graphene semiconductor being 10 times that of silicon. This new type of semiconductor can be used to manufacture smaller and faster electronic devices or for quantum computing. The research was published in the journal “Nature” on January 3.
A semiconductor is a material that conducts electricity under specific conditions and is a fundamental component of electronic devices. Graphene, on the other hand, is a single-layer sheet-like structure made up of carbon atoms, with a thickness of only one carbon atom, making it a two-dimensional material. Graphene, in its natural state, is neither a semiconductor nor a metal.
A research team led by Walter de Heer, a physics professor at the Georgia Institute of Technology, developed a graphene semiconductor. This semiconductor is compatible with traditional microelectronics processing methods, a necessary condition for replacing silicon.
Walter de Heer began exploring the semiconductor potential of carbon-based materials early in his career, shifting his focus to graphene research in 2001. He noted that graphene is an extremely robust material that can handle very large currents and aimed to introduce graphene’s characteristics into electronics.
The research team produced a single-crystal graphene grown on the surface of a silicon carbide crystal, known as epitaxial graphene. They found that when produced correctly, epitaxial graphene forms a chemical bond with silicon carbide and exhibits semiconductor properties. Over the next decade, they refined this material at the Georgia Institute of Technology, later collaborating with the International Research Center for Nanoparticles and Nano Systems at Tianjin University.
Researchers placed atoms on graphene to observe whether the material behaved as a good conductor through electron doping. Measurements revealed that the electron mobility of the graphene semiconductor is 10 times that of silicon, meaning electrons move with very low resistance, indicating faster computing speeds in electronics. “It’s like driving on a gravel road versus driving on a highway,” said Walter de Heer.
The “bandgap” is a critical electronic characteristic that allows semiconductors to switch. It can open or close when an electric field is applied, and this is the working principle of all transistors and silicon electronics. Graphene lacks an inherent bandgap, and a key challenge in graphene electronics research has been how to open and close it to make it work like silicon. Marey, a professor at the International Research Center for Nanoparticles and Nano Systems at Tianjin University and a co-author of the paper, stated that the team’s technology achieved a bandgap, a crucial step in realizing graphene electronics.
The Georgia Institute of Technology stated that the graphene semiconductor developed by the team is currently the only two-dimensional semiconductor with all the necessary characteristics for nanoelectronics, and its electrical characteristics far exceed any other two-dimensional semiconductor currently under development. Epitaxial graphene could lead to a paradigm shift in electronics, utilizing the quantum mechanical wave nature of electrons, a necessary condition for quantum computing.
Andre Geim, the Nobel Prize-winning physicist known as the “father of graphene,” stated in 2022 that graphene is a “nickname” for a large class of materials with potential in various industries. Graphene is hailed as a new material driving the development of the electronics industry. Although there doesn’t seem to be any revolutionary applications currently, it is believed that in certain areas of the electronics industry, this material has advantages over silicon. “While there may not be any revolutionary applications at the moment, through continuous improvement, product quality will further improve, leading to revolutionary applications… but we still need to wait for 10 or even 20 years,” Geim said.