Introduction to the Graphene-based Semiconductor
Scientists have created the world’s first working graphene-based semiconductor, which could pave the way for chips that power much faster PCs and quantum computers in the future.
Advantages Over Silicon
The new semiconducting material, made from epitaxial graphene, allows for more mobility than silicon, meaning electrons move with less resistance. Transistors made in this way can operate at terahertz frequencies — 10 times faster than the silicon-based transistors used in chips used today, the researchers wrote in a study published Jan. 3 in the journal Nature.
Essential Properties of Semiconductors
Semiconductors have properties of both conductors and insulators. At the right temperature range, electrons move through the semiconductor material — but only if a certain amount of energy is applied.
Limitations of Silicon in Computing
Almost every chip uses a semiconductor made from silicon, but the material is reaching its limits. These limits include the maximum speed at which transistors can “switch” between their on-off positions, the heat they generate through resistance, and the smallest size people can make them. This means the rapid advancements we’ve seen throughout the history of computing are beginning to slow.
Graphene’s Superior Conductive Properties
Graphene, made from a single layer of carbon atoms tightly bound in a hexagonal lattice, is a better conductor than silicon, meaning electrons move with less resistance through the material. Despite its favorable properties, graphene has never been harnessed in electronics because of the lack of a “band gap”. Band gaps are what enable transistors to switch on and off.
Creating a Functional Graphene Semiconductor
To function as a working transistor, the graphene must be treated in some way, but in the past, this has damaged its properties. The researchers overcame this challenge by fusing graphene onto silicon carbide using special furnaces and a special heating and cooling process. By doping the graphene, they created a functional graphene semiconductor with a band gap.
Potential for Integration and Quantum Computing
Not only is this the first graphene-based semiconductor to work, but it can also be integrated into existing manufacturing processes. Graphene-based semiconductors also have potential future use in quantum computing.
Quantum Mechanical Properties and Future Research
“Like light, electrons in graphene have quantum mechanical wave-like properties that can be accessed in devices, particularly at very low temperatures,” de Heer said. This is an area the scientists hope to explore in subsequent research, but it remains to be seen whether graphene-based semiconductors can work better than the current superconducting technology, which is used in the most advanced quantum computers.