Silicon is dead. Long live, carbon nanotubes.
In transistors, size matters — a lot. You can’t squeeze more silicon transistors (think billions of them) into a processor unless you can make them smaller, but the smaller these transistors get, the higher the resistance between contacts, which means the current can’t flow freely through them and, in essence, the transistors and chips built based on them, can no longer do their jobs. Ultra-tiny carbon nanotube transistors, though are poised to solve the size issue.
