IBM has designed a high-speed circuit using graphene, which offers very high speeds and can be used to produce high performance devices.

The new circuits come just over a year after IBM first demonstrated a graphene transistor, and marks a breakthrough in research into the super-fast material.
Although the new circuits are an important milestone, the material is not yet ready to replace existing transistors or processors since they don’t have the same physical properties.
Graphene’s key advantage lies in the very high speeds in which electrons propagate, which is essential for achieving high-speed, high-performance next generation transistors.
Graphene is a single atom-thick layer of carbon atoms bonded in a hexagonal honeycomb-like arrangement. This two-dimensional form of carbon has unique electrical, optical, mechanical and thermal properties and its technological applications are being explored intensely.
Uniform and high-quality graphene wafers were synthesized by thermal decomposition of a silicon carbide (SiC) substrate. The graphene transistor itself utilized a metal top-gate architecture and a novel gate insulator stack involving a polymer and a high dielectric constant oxide. The gate length was modest, 240 nanometers, leaving plenty of space for further optimization of its performance by scaling down the gate length.