For those who worry about the supposed apocalypse that will happen once silicon transistors can't be squeezed any further:
Graphene transistors clocked at 26GHz
IBM has seen the future of computing and it may not involve silicon. Instead the company has been looking at graphene, the single atom-thick sheets of carbon that has materials scientists entranced by its dazzling array of amazing properties. If graphene ever becomes the material of choice for a new generation of superfast chips, then the work of Yu-Ming Lin and buddies at the IBM T. J. Watson Research Center in upstate New York may well turn out to be one of the foundations of that revolution. Today, they say they’ve built the high quality graphene transistors and clocked them running at 26 GHz. That doesn’t quite knock silicon off its perch–the fastest silicon transistors are an order of magnitude faster than that but the record is held by indium phosphide transistors which have topped 1000 GHz. Still, 26 GHz isn’t bad for the new kid on the block. It took silicon 40 years to get this far. By contrast, the first graphene transistor was built only last year. As the team puts it: “The work represents a significant step towards the realization of graphene-based electronics.” Ref: arxiv.org/abs/0812.1586: Operation of Graphene Transistors at GHz Frequencies
Of course this is just one option. There are many ways we can keep on Moore's Law and even faster than Moore's Law without silicon transistors. The most promising is probably quantum computing but that's very complex and it may be well beyond 2020 once we master it and start creating wonder quantum computers...