Can Graphene Replace Silicon Chips?
A new era opens in electronics. Joint research by China and the USA has created the first graphene material with semiconducting capabilities and electrical mobility 10 times greater than that of silicon.
A research team from the Georgia Institute of Technology and Tianjin University in China, led by physics professor Walter de Heer, has achieved a major milestone in electronics: the creation of the first functional semiconductor made from graphene. This result was obtained by depositing graphene on a silicon carbide substrate, resulting in a semiconductor with electron mobility 10 times higher than that of silicon.
Graphene will have a huge responsibility: changing electronics
Graphene is a single layer of carbon atoms arranged in a hexagonal lattice, forming a one-atom-thick honeycomb structure. Therefore, it belongs to the category of two-dimensional, or 2D, materials.
Graphene's exceptional properties, such as its high electrical conductivity, flexibility, and transparency, have already paved the way for its use in various electronic applications.
Precisely ecause of its high electrical conductivity, graphene has so far lacked a characteristic of silicon: an adequate band gap.
The band gap is the energy difference between the valence band and the conduction band of a material. In simpler terms, it signifies the energy required to transition an electron from the valence band, where it cannot contribute to conduction, to the conduction band, where it can participate in the flow of electric current.
Silicon possesses a band gap naturally present within its crystal structure. This allows us to manipulate its electrical properties without necessarily introducing impurities or foreign atoms through a process called doping.
Having an adequate band gap in a semiconductor allows the material to be used to represent fundamental 'on/off' states, which are crucial in the field of electronics.
In a landmark advance, researchers at the Georgia Institute of Technology and Tianjin University in China have unlocked the true potential of graphene as a semiconductor. Through a sophisticated fabrication process, they successfully manipulated the electronic properties of graphene.
After optimizing the epitaxial growth process within specialized furnaces, researchers successfully produced high-quality epitaxial graphene, a single layer seamlessly integrated with the crystal structure of the silicon carbide wafer. This intimate bonding doesn't just involve "clinging" but forms strong covalent bonds, crucial for achieving the desired properties. Extensive testing confirmed that this epitaxial integration significantly modifies the electronic structure of graphene.
Experiments have indeed revealed that this new graphene semiconductor exhibits electron mobility 10 times higher than that of silicon.
Since silicon is getting close to its limits, and we're asking for faster processing in smaller devices, the new idea of using graphene as a semiconductor is really important for the electronics industry.
However, if we have a material like graphene and can't produce it on a large scale with the right economies, it might not spread widely. Fortunately, with the graphene semiconductor, this isn't an issue. De Heer states that its production aligns with conventional microelectronics processing methods. This is crucial for any real alternative to silicon.
Great news
ReplyDelete