Researchers have developed a new nanoelectronic platform based on graphene – a single sheet of carbon. An urgent need in the field of nanoelectronics is the search for materials that can replace silicon. Graphene has looked promising for decades. But his ability fell by the wayside, due to the destructive treatment methods and the lack of new electronic systems to accommodate him. With silicon approaching its peak to accommodate rapid assembly, the next big nanoelectronics platform is now more important than ever.
Walter de Heer, Regents Professor at the School of Physics at the Georgia Institute of Technology, made an important step in making the case for a successor to silicon. De Heer and his colleagues have developed a new nanoelectronic platform based on graphene – a single sheet of carbon.
The technology is compatible with conventional microelectronics manufacturing, a prerequisite for any material that can replace silicon. During their research, published in Nature Communications, the team may have discovered something new. Their findings could lead to the creation of smaller, faster, more efficient and durable computer chips, and have implications for quantum and advanced computing. “The strength of graphene lies in its flat, two-dimensional form with the strongest chemical bonds known,” said de Heer. “It is clear from the beginning that graphene can be reduced much more than silicon – allowing for smaller devices, while it works at higher speeds and produces less heat. This means that in principle more devices can be packed on a single graphene chip than on silicon.
In 2001, de Heer proposed another type of electronics based on epitaxial graphene, or epigraphene – a layer of graphene that was found to grow simultaneously on top of silicon carbide crystals, a semiconductor used in advanced electronic devices. At that time, researchers found that electricity flows without resistance through the edges of epigraphene and that graphene devices can be connected safely without metal wires. This combination enables electronic models based on the unique thermal properties of graphene electrons.
“Quantum interference has been observed in low-density carbon nanotubes, and we expect to see a similar effect in epigraphene ribbons and lattices,” said de Heer. “This important activity of graphene is not possible in silicon.”
Create a platform
To create a new nanoelectronics platform, the researchers created a modified version of epigraphene with silicon carbide crystals. Together with researchers from the Tianjin International Center for Nanoparticles and Nanosystems at Tianjin University, China, they created a unique piece of silicon carbide from flat silicon carbide crystals. The graphene itself is grown in de Heer’s lab at Georgia Tech using a patented oven.
The researchers used electron lithography, a technique commonly used in microelectronics, to create graphene nanostructures and bond them to silicon carbide chips. This process makes it stable and closes the edges of graphene with iron, which will react with oxygen and other gases that can prevent the movement of charges around the edges.
Finally, to measure the electronic properties of their graphene platform, the team used a cryogenic device that allows them to record its properties from near zero to high temperatures.
A look at the edge state
The electrical charge the team observed at the edge of graphene’s state resembles a photon in an optical fiber that can travel long distances without dispersing. They found that the charge travels tens of thousands of nanometers along its surface before dispersing. Graphene’s electrons in previous technologies can travel about 10 nanometers before they hit a small imperfection and scatter in different directions.
Claire Berger, professor of physics at Georgia Tech and lead researcher said, “The unique thing about electric charges at the edge is that they stay at the edge and move forward at the same speed. at the Center National de la Recherche Scientifique de Grenoble, France.
In metals, an electric current carries a negative charge. But contrary to the expectations of the researchers, their measurements suggest that neither electrons nor holes carry the liquid (the term for real quasiparticles indicates the absence of electrons). Instead, it is a rare object that has no charge or energy, moving the water without resistance. A portion of the quasiparticle hybrid was observed to move in the opposite direction of the graphene portion, although it is the same material.
The unique properties indicate that the quasiparticle may be one that scientists have been hoping to exploit for decades – the mysterious Majorana fermion predicted by the Italian physicist Ettore Majorana in 1937. “Creating electronic devices using this quasiparticle novel and seamless graphene network is a game-changer,” said de Heer.
It will be another five to 10 years before we have the first graphene-based electronics, according to de Heer. But thanks to the group’s new epitaxial graphene platform, the technology is closer than ever to crowning graphene as a successor to silicon.
