Scientists break new barrier in data storage capacity

Millipede uses heated silicon tips to form indentations in a layer of plastic on a silicon chip. IBM

Scientists in Zurich have devised a way of cramming up to 20 times more data on to a silicon chip than has been possible up to now.

Researchers at IBM say they have demonstrated how one trillion bits of information can be stored on a single square inch of silicon – that is 20 times more than the densest magnetic storage available today.

This density would be enough to store 25 million textbook pages on a surface the size of a postage stamp.

The research project, called Millipede, has also made progress on rewriting capability. “The scientists were able to demonstrate that it is possible to erase and overwrite individual bits,” IBM spokesman, Martin Hug, told swissinfo.

No major obstacles

Millipede uses heated silicon tips to form indentations in a thin layer of plastic on a silicon chip.

Each indentation, representing a bit of data, is 10 millionths of a millimetre wide. By varying the heat and measuring changes in electrical resistance as the tips drop into an indentation, the data can be read, erased and overwritten.

Eventually the process should be able to create indentations only a single atom wide.

“There have been no show-stoppers so far,” said Hug. “There are many technical details which have to be addressed but there is nothing the scientists think will be a major obstacle to really getting this new technology working.”

Punch cards

The technique, first announced in 1999, uses tiny “punch cards” to store and read bits of data. The punch-card technique could produce storage for a whole range of small devices using low power consumption like mobile phones, cameras, notebook computers and handheld devices.

IBM scientists hope to have a fully functioning prototype by early next year. The prototype will have more than 4,000 tips operating simultaneously to create and read indentations in a patch, seven millimetres square.

“There is no decision at the moment to go into product development,” said Hug. “But if this happens and this could be decided by next year, then it could take another two to three years at best before a product is on the market and that would be in the 2005 timeframe.”

by Vincent Landon