Ultra-fast semiconductor chipmakers have long awaited compounds that would increase chipset speed. To build a faster chipset, they needed a suitable material that exhibits higher charge mobility than silicon. Although several high-charge mobility compound semiconductor materials are available, they are costly and don’t allow the use of insulator materials that would make mass production possible.
Now, the wait is over. NASA’s Langley Research Center has patented a fabrication method for the first ever rhombohedrally grown, lattice-matched SiGe semiconductor alloy structure. This innovation, which won a 2009 R&D 100 Award, enables wafer-scale mass production of ultra-fast chipsets exhibiting charge mobility of more than 3,000 cm2/Vs—well beyond the state of the art for semiconductor chips.
How Much Faster?
Conventional silicon-based chipsets have achieved clock frequencies of approximately 144 gigahertz. NASA’s fabrication method can produce chipsets that offer clocked speeds of up to 308 gigahertz with much better performance. Plus the chipsets can use a conventional silicon oxide insulator, which enables wafer-scale mass production.
Other benefits of NASA’s innovation include:
- Better performance: Improves performance with new lattice-matched conditions
- Superior quality: Produces superior quality, graded, indexed SiGe layers with fewer defects
- Low implementation cost: Uses existing silicon fabrication facilities for production
- Mass production: Enables wafer-scale mass production through compatibility with conventional SiO2 insulators
- Versatile: Allows varying material thicknesses including Si/Ge/SiGe quantum wells
For information about licensing this technology, contact: