GaAs Powered
Research at Lucent Technologies’ Bell Lab-oratories in Murray Hill, N. J., may be hastening the onset of a new era in electronic materials. Scientists have long known that electrons travel much faster in gallium arsenide (GaAs) than in silicon. But GaAs has found limited use in computing devices, partly because of the difficulty of fabricating suitable transistors.
Silicon chips use metal-oxide-semiconductor field-effect transistors, or MOSFETs. Most GaAs devices now in use (principally in wireless communications) are MESFETs, lacking the oxide. To tap the advantages of GaAs fully will require MOSFETs, which use less power. Bell Labs took the first step two years ago, but its prototypes were woefully inadequate-current fluctuated by 20 percent over a few hours. In the new GaAs devices, however, current drifts only about 1.5 percent after 200 hours. One key benefit: longer time between cell phone rechargings.
