IBM builds world's smallest circuit
Boffins at IBM have prototyped what is believed to be the world's smallest working computer circuits, using an innovative approach in which individual molecules move across an atomic surface like toppling dominoes.
The new "molecule cascade" technique enabled the scientists to make working digital-logic elements about 260,000 times smaller than those used in today's most advanced semiconductor chips, according to IBM.
The circuits were made by creating a precise pattern of carbon monoxide molecules on a copper surface. Moving a single molecule initiates a cascade of molecule motions, just as toppling a single domino can cause a large pattern to fall in sequence.
The scientists then designed and created tiny structures that demonstrated fundamental digital-logic building blocks (OR and AND functions, data storage and retrieval) and the "wiring" necessary to connect them into functioning computing circuitry.
The most complex circuit they built - a 12 x 17-nanometer three-input sorter - is so small that 190 billion could fit atop a standard pencil-top eraser. A nanometer is a billionth of a meter; or the length of five to 10 atoms in a line.
"This is a milestone in the quest for nanometer-scale computer circuitry," said Andreas Heinrich, a physicist at IBM's Almaden Research Center in San Jose, California, and one of the lead authors of the research article published in the online edition of Science Magazine, Science Express.
"The molecule cascade is not only a novel way to do computation, but it is also the first time all of the components necessary for nanoscale computation have been constructed, connected and then made to compute. It is way smaller than any operating circuits made to date."
Heinrich, IBM Fellow Don Eigler (who laid the theoretical foundations for the work two years ago) and colleagues Christopher Lutz and Jay Gupta are continuing their exploratory research to find additional nanometer-scale computing systems based on the cascade mechanism.
The research is still at an early stage of development and it's unclear, as yet, if and when the technology might become commercially available. ®