Moore's Law lives

Or do they?

For years technologists have debated the prospects for longevity of Moore's Law, an observation made by Intel co-founder Gordon Moore in 1965 that the number of transistors per square inch on an integrated circuit doubles every year to two years.

Video: Life span of Moore's Law even amazes the author
--Intel co-founder Gordon Moore

Over the past 40 years this observation, first published in an article for Electronics magazine, has become a defining principle of computing that has driven the industry to build computers and cell phones that are cheaper, faster, more powerful and, very often, more compact.

At a symposium hosted on Friday by the Marconi Society in New York City, where Gordon Moore is being honored with a lifetime achievement award, scientists and engineers discussed just how long Moore's observation will hold.

Moore himself said he is amazed that his prediction has held true even this long.

"I never expected it to be especially accurate," he said during a panel discussion. "It's amazing that a throwaway article has established a history of its own."

The success of Moore's predictions has created some problems. After decades of doubling transistors, a single chip now contains several million transistors. Multibillion-dollar factories have been built to produce these increasingly complex chips. Shrinking the size of transistors and the copper wires that connect them to fit more densely on a chip has also led to problems like electric leakage, increased power consumption and processors that generate a fair amount of heat.

Not to mention the fact that physics at some point limits how much transistors can be shrunk.

"My intellect tells me that it will end at sometime," said Leonard Kleinrock, professor of computer science at UCLA and creator of the basic principle of packet switching. "The size of an atom, the size of my fingers, and the capability of my eyes will at some point get in the way."

Transistors consist of four basic parts: a source (which stores electrons), a drain (where they go to create a "1" signal), a gate and a gate oxide (which controls the flow from the source to the drain). After several shrinks, the gate oxide is only about 10 atoms thick, in some cases, meaning further shrinking is not possible without an arduous chemical or architectural makeover.

But many scientists in the industry today believe that new materials and new methods will be developed to extend Moore's Law. Gradually, chips could move away from silicon to other materials such as carbon nanotubes.

Another strong possibility is that silicon continues as the medium of choice, but new materials get added to it. Some technologists, such as Federico Faggin, who developed the method for manufacturing metal oxide semiconductors, said that chips may be built in three dimensions, with components layered on top of each other like skyscrapers.

"We've never used a third dimension," he said. "So we will have to learn to build up."

Other technologists say that Moore's Law will have to continue, because society demands it.

"Can the end of Moore's Law really happen?" said Robert Lucky, Marconi Society chairman and former director of Bell Laboratories. "We all live off this trillion-dollar industry, so what would happen to the industry if it ended? We all demand more. Whether that means going to carbons nanotubes or 3D, I don't know."