Silicene Could Beat Graphene to Market
Silicene, a single-atom thick layer of silicon, could beat graphene to the components market due to the industry’s familiarity with silicon and its properties.
Graphene is a truly wondrous molecular structure. Since its discovery a few years ago, scientists have become more and more excited about the possibilities graphene affords. It is the most conductive material in the known universe with surprising optical qualities, and IBM has shown that graphene could allow computers to operate close to the terahertz range (one terahertz, or THz, is equal to roughly 1,000 gigahertz, or GHz). The problem is that graphene does not have a band gap. A band gap is the difference in energy from an on state, where electrons are flowing through a circuit, and an off state, where no electron motion is possible. Without a band gap, it’s extremely difficult to build transistors, which have to be able to switch from “on” to “off” and back again very quickly. Some progress in creating a band gap in graphene has been made, but the material is still years or possibly decades away from being used in current computer components.
Now, research has been released from multiple research groups around the planet announcing the creation of silicene, a one-atom thick layer of silicon equivalent to graphene. This presents a lot of promise to researchers and engineers, because silicene, being based on silicon, should be compatible with current electronics and electronic fabrication techniques. The research groups created the silicene sheet by condensing silicon vapor onto a silver substrate. Currently, we only have proof that silicene exists, as the scientists observed it through a scanning tunneling electron microscope, but they theorize that silicene should have highly desirable electrical properties, perhaps even close to the electrical conductivity of graphene.
The next step is to grow silicene on an insulator, so that it can be used to create a circuit. At least four research groups managed to successfully create silicene on a silver substrate, so it’s highly likely that they’re working to find an insulator that will allow them to repeat their success. With silicon reaching the physical limits of its capabilities sometime in the next decade, silicene could be exactly what the electronics industry needs.