Page IV: The only question is which approach will work best -- using molten silicon, designer molecules, or maybe protein globules?
Mayes came up with the idea for the company while working on a doctorate, at the University of Bristol, on the interaction between biological agents and inorganic molecules. Bricks and seashells are structurally quite dissimilar, he pointed out, but made of the same material. By exploiting naturally occurring biological phenomenon, NanoMagnetics hopes to reduce the cost of manufacturing storage devices.
True to its roots, the company still obtains its carrier protein, ferritin, the old-fashioned way.
"We get it from animal sources," he said. Humans produce ferritin. But instead of getting it from employees, NanoMagnetics buys its ferritin from collagen manufacturers who get it from cows. The company is currently looking at ways to produce it in the lab "because my wife is a vegetarian," Mayes joked.
In terms of size, ferritin is relatively small. A single sphere measures 12 nanometers in diameter, while the inner cavity measures 8 nanometers. By contrast, an AIDS virus measures around 50 nanometers across. NanoMagnetics is also looking at DNA protection system (DPS) proteins, which are even smaller, as carriers.
Seagate, IBM and others have performed similar experiments by coating magnetic particles in a substance similar to olive oil. Proteins, however, can withstand higher temperatures and therefore maintain their shape and relative position in an array better during high manufacturing temperatures, he said.
While the company has tinkered with different business models, it is now aiming at working with established manufacturers to incorporate the technology into finished products. Agreements may be announced toward the end of the year that could lead to products by the end of 2006. A large Asian manufacturer is currently testing it.
Conceivably, the material could be used to create multiple-gigabyte chips that would allow mobile phones to store movies and sitcoms, Mayes said.
Like other companies in this space, however, the uphill challenge is in persuading manufacturers to adopt it. NanoMagnetics' active particles are applied with an inkjet sprayer. Hard-drive makers now use chemical sputterers to apply coatings. Although ink jet spraying will be cheaper, convincing producers to spend money on new methods isn't easy.
"Everyone is a step away from the dustbin," he joked. Most likely, NanoMagnetics will have its first commercial success in water purification, he said. The same particles can be used in the reverse-osmosis process.
Ribbons of nanotubes
Woburn, Mass.-based Nantero has come up with a way to make transistors, the on-off switches inside chips, with carbon nanotubes, hollow tubes of carbon atoms that exhibit a number of remarkable properties.
The company's technology exploits two of these properties: the bendable nature of nanotubes and the strong attraction carbon atoms exhibit for one another.
In Nantero's memory design, ribbons of carbon nanotubes are suspended over pieces of carbon. In the "off" state, the ribbon of nanotubes does not touch the carbon. In the "on" state, the nanotube bends downward and then adheres to the carbon. Electricity flows and the memory cell registers as a 1, in data terms. An electric charge can separate or connect the ribbons.
Nantero's memory is faster than static random access memory (SRAM), an embedded form of memory used for caches on processors, CEO Greg Schmergel said.
Nantero's success in licensing its technology -- LSI Logic and aerospace specialist BAE Systems have taken out licences -- lie in a radical shift in architecture that was implemented during the past year. Initially, Nantero proposed making memory cells in which a single nanotube would connect or detach from a perpendicular nanotube below it.
While this would allow for incredibly dense memory chips, most analysts and scientists doubted that the company could come up with a way to erect millions of uniform, microscopic crossbars on a sliver of silicon less than a few square centimeters across.
In the new architecture of the company's chips, a layer of nanotubes is spread onto a piece of carbon. Engineers then use conventional lithography to "draw" electrical contacts that are connected to each other by the thick ribbons of nanotube material and the substrate. This method, however, eliminates many of the cost and size advantages, at least for now.
"We won't be achieving thousandfold density improvement just yet," Schmergel said.
And, like all other new memory advocates, the company will have to face the skepticism of an industry that has seen it all.
"A lot of people are looking for the next material, but we think they already found it in silicon," said Dan Steere, vice president of marketing and sales at Matrix Semiconductor.
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