A research team from IBM and the Georgia Institute of Technology has demonstrated the first silicon-germanium transistor able to operate at frequencies above 500 GHz. Though the record performance was attained at extremely cold temperatures, the results suggest that the upper bound for performance in silicon-germanium devices may be higher than originally expected.
Ultra-high-frequency silicon-germanium circuits have potential applications in many communications systems, defense systems, space electronics platforms, and remote sensing systems. Achieving such extreme speeds in silicon-based technology – which can be manufactured using conventional low-cost techniques – could provide a pathway to high-volume applications. Until now, only integrated circuits fabricated from more costly III-V compound semiconductor materials have achieved such extreme levels of transistor performance.
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Looks like there's still some kick in the old technology yet. The frequency difference between this and what is in our desktops now is like the difference between a 286 and an old pentium. I'd say we can squeeze a few more generations out of the old fab techniques yet.
