Nov. 3. 2006 — Nantero Inc., a Woburn, Mass., company using carbon nanotubes for the development of next-generation semiconductor devices, announced it has resolved the major obstacles that had been preventing carbon nanotubes from being used in mass production in semiconductor fabs.
Nanotubes are widely acknowledged to hold great promise for the future of semiconductors, but most experts had predicted it would take a decade or two before they would become a viable material. This was due to several historic obstacles that prevented their use, including a previous inability to position them reliably across entire silicon wafers and contamination previously mixed with the nanotubes that made the nanotube material incompatible with semiconductor fabs.
Nantero announced it has developed a method for positioning carbon nanotubes reliably on a large scale by treating them as a fabric which can be deposited using methods such as spincoating, and then patterned using lithography and etching. The company said it has been issued patents on all the steps in the process, as well as on the article of the carbon nanotube fabric itself, US Patent No. 6,706,402, “Nanotube Films and Articles,” by the U.S. Patent and Trademark Office.
The patent relates to the article of a carbon nanotube film comprised of a conductive fabric of carbon nanotubes deposited on a surface. Nantero has also developed a method for purifying carbon nanotubes to the standards required for use in a production semiconductor fab, which means consistently containing less than 25 parts per billion of any metal contamination.
With these innovations, Nantero has become the first company in the world to introduce and use carbon nanotubes in mass production semiconductor fabs.
The company is developing NRAM — a high-density nonvolatile random access memory device intended for use as a universal memory. The company says it can be manufactured both as standalone devices and as embedded memory in application- specific devices such as ASICs and microcontrollers.