The standard semiconductor for processors is silicon, which is expected to eventually reach its functional limits for applications that require increasingly small devices. Carbon nanotubes have often been thought to be an ideal successor to silicon for processor fabrication. The material can replace silicon wafers in manufacturing while retaining existing fabrication infrastructure. Carbon nanotubes could improve on silicon's performance through the material’s superior heat dissipation and a theoretical order of magnitude increase in electrical efficiency.
A carbon nanotube computer could, in theory, be faster and smaller. However, the material is challenging to work with. For example, carbon nanotubes are made on a quartz substrate and can grow erratically, with some tubes conducting electricity like a metal.
On September 27, 2013, researchers at Stanford University announced the world’s first carbon nanotube-based computer: a one-bit 178-transistor proof-of-concept processor. The prototype computer operates at 5 volts and is not very power-efficient. Nevertheless, given time, it can perform any calculation.
Announcing the first carbon nanotube computer: