IBM Carbon Nanotube Breakthrough Could Mean Faster, Better Devices
The premise behind Moore's Law -- which says technology advances tend to double the number of transistors on a silicon chip every two years -- has shown signs of slowing down recently because of physical limitations. But an engineering breakthrough announced yesterday by IBM could give that law new life by replacing silicon transistors with chips made with carbon nanotubes.
A semiconductor material made from single-atom sheets of carbon rolled into tubes, carbon nanotubes could offer significant advantages over the silicon used in computing chips today, IBM said. Its latest research could pave the way for mobile devices that stay charged longer and higher-performing computers that could handle big data analytics faster and more efficiently, Big Blue said.
Until now, making chips ever smaller with either silicon or carbon nanotubes resulted in increasing electrical resistance, which hurt performance. IBM researchers, however, said they have developed a new method -- "akin to microscopic welding" -- that lets them shrink the size of transistor contacts down to below 10 nanometers (for comparison, the size of the smallest bacteria is around 200 nanometers) without seeing performance deteriorate.
Goal: Carbon Nanotube Tech in 10 Years
"These chip innovations are necessary to meet the emerging demands of cloud computing, Internet of Things and big data systems," said Dario Gil, vice president of science & technology at IBM Research, in a statement. "As silicon technology nears its physical limits, new materials, devices and circuit architectures must be ready to deliver the advanced technologies that will be required by the cognitive computing era."
IBM last year announced it was committing $3 billion to a five-year program focused on chip research and development. Earlier this summer, the company said those efforts in a partnership with other research organizations had resulted in an ultra-tiny computer chip that's 50 percent smaller than the smallest chips in use today.
This week's research breakthrough "shows that computer chips made of carbon nanotubes will be able to power systems of the future sooner than the industry expected," Gil said. This brings us a step closer to the goal of a carbon nanotube technology within the decade."
Formulated by Intel co-founder Gordon E. Moore in 1965, Moore's Law has generally held true for advances in computing technology for nearly half a century. However, in a conference call to discuss Q2 earnings this summer, Intel CEO Brian Krzanich acknowledged that the pace of innovation has recently begun to slow, and that it was taking the company longer to achieve successive improvements in chip technology.
"The last two technology transitions have signaled that our cadence today is closer to two and a half years than two," Krzanich said at the time.
IBM says its carbon nanotube research, which is detailed in today's issue of the journal Science, could help Moore's Law get back on track. Its innovation rests on a new way to bond the metal molybdenum to the ends of carbon nanotubes, which reduces the increased resistance problems that previously arose when carbon transistors were made smaller than 20 nanometers.
"Key to the breakthrough was shrinking the size of the contacts without increasing electrical resistance, which impedes performance," noted IBM research scientist Shu-Jen Han. "Until now, decreasing the size of device contacts caused a commensurate drop in performance."
The next challenges will be finding better ways to purify carbon for nanotube-based chips and to manipulate those nanotubes "so we can build billions of tiny transistors on a single chip," Gil said, adding that researchers are currently working on both of those challenges.
"We've made great progress in purifying carbon, and we're now within striking distance of the answers we need," Gil said. "We're still seeking a breakthrough in the placement of nanotubes. That's an incredibly difficult puzzle to solve."