Friday, June 27, 2008

IBM's "Noise Free" Nano Lab

Continued from page 1

By Duncan Graham-Rowe

For example, IBM is looking at building transistors from nanowires, using tiny magnetic forces exerted by electrons to store information, and slowing and bending light in ways that make it possible to carry out computations with photons instead of electrons.

But with these new technologies come new challenges. "Once you move into atomic-scale research, you are dealing with very low energy levels, and so you need very sensitive instruments," says Kaiserswerth. And the more sensitive the instrument, the more responsive it is to disturbances in the environment. "Every time we bought a new piece of equipment," says Paul Seidler, IBM Zurich's science and technology manager, "we would find ourselves having to think hard about which lab was most suitable."

"And as nanotechnology progresses in making ever smaller structures that demand higher precision, many labs will increasingly find this a problem," says Kaiserswerth. Zhang agrees. "It's something the industry will have to address," he says.

Each lab in IBM's new facility will have test benches mounted on separate concrete blocks, elastically supported by pneumatic dampers. These in turn will be mounted on vibration-absorbing high-mass concrete slabs. This double floor will eliminate even vibrations caused by people entering the room.

Similarly, the labs will effectively be encased in cages that act like passive electromagnetic shields to protect against permanent electromagnetic fields, such as those caused by nearby railways or other labs. Sensor-based active shielding will compensate for any periodic electromagnetic disturbances. "We can shield down to five nanotesla, or one-10,000th of the earth's magnetic field," says Kaiserswerth.

"This is the next level of precision," says Seidler. "In many respects, it's an indication that nanoelectronics has arrived."