Abstract :
\´Solid-state\´ and \´no moving parts\´. They are the phrases manufacturers use to let us know that stuff is reliable. Researchers such as Professor Asen Asenov of the University of Glasgow know, however, that solids aren\´t all that solid. The core problem is variability. Experts speaking at the recent international conference on CMOS Variability in London, organised by the UK\´s National Microelectronics Initiative (NMI), see the 22 nm process as a critical juncture in the evolution of the silicon chip. Due to start production in 2012, the process will use transistors so small that Asenov claims: "You can count the dopant atoms. You can even count the number of silicon atoms in there. The random placement of dopant atoms in the channel of a transistor can lead to big changes in performance, even between two devices sitting within tens of nanometres of each other on a die, to the extent that one works and the other a failure. Size is not the only cause of variability.
