Sometime next year, you may be able to throw out your old memory chips and replace them with new faster and cooler carbon nanotube (CNT) memory. Greg Schmergel, co-founder, president and CEO of Nantero told TG Daily that his company is on track to bring drop-in memory sometime next year. Using carbon nanotubes, the new memory will allow future computers to instantly turn on, use less electricity and run cooler.
Carbon nanotubes (CNT) are believed by scientists to play a major role in scaling semiconductors and digging deeper into nanotechnologies. For example, Fujitsu recently said that it will use the technology for semiconductor heatsinks, research firm nanomarkets said that CNTs will be a center piece of future LCDs, Motorola is working on CNT-based fuel cells and virtually any semiconductor firm, including Infineon and Intel, develops the technology for future transistor manufacturing.
Nantero, however, is the first company that in fact announces a real-world CNT computer product that may be available for purchase in the not too distant future. Schmergel told TG Daily that CNT memory will combine the speed of SRAM with the non-volitility of flash. “You can have an instant on computer, instead of waiting a few minutes for your computer to boot up,” he said. In addition, he noted that unlike regular flash memory, which has a limited number of read/write cycles before dying [about 1,000,000 cycles – Ed], CNT memory achieve a much longer life. “Any other material would break, but carbon nanotubes allow a virtually infinite number of write cycles,” Schmergel said.
Nantero’s memory will use CNTs that are suspended above electrodes. The CNTs are moved up or down by an electric charge and their position determines whether the bit is registered as a one or zero. After moving, no further electricity is needed because the tube is held by molecular forces. Schmergel explains, “After we move the tube, it comes into contact with metal. Van der Waals forces keep it in place pretty much forever, until we hit it with another charge,” he explained.
Schmergel was not able to provide us exact numbers of density and performance of CNT memory modules, but said that “eventually we could put one trillion bits on something the size of your fingertip.” In terms of speed the new memory will reach up to “two billion cycles per second,” according to Schmergel. Nantero doesn’t expect any incompatibility issues, once its memory is available as modules will use the same connectors and be a drop-in replacement for current chips. “The motherboard manufacturers won’t need to redesign anything, just pop out the old memory and put in ours,” said Schmergel.
Nantero does not run its own CNT manufacturing, but opted to buy CNTs from “several” manufacturers around the world. “We buy by the gram and if you are going to make enough chips for the world, you will need kilograms of them.” A very small quantity is used to make each chip and while Schmergel couldn’t tell us exactly how many chips can be made with a gram of CNTs, he did say, “It’s a lot!”
The small size of carbon nanotubes can also complicate manufacturing. Schmergel explained that it can be difficult removing contamination from the purchased CNTs and that there are varying qualities of nanotubes. “Nanotubes are generally made in a pretty dirty environment,” says Schmergel. Nantero must remove all the contamination before placing them in the semiconductor factory. “The tubes come mixed with several percent of metal. Usually it’s iron with some nickel and cobalt,” says Schmergel. The main reason for the iron contamination is that the tubes are grown out of iron nanoparticles. “It’s a long detailed process and very tricky. You have to get rid of the iron, without damaging the tubes,” says Schmergel.
In addition to contamination problems, CNTs are difficult to position in the right place. Realizing that fact, Nantero takes another approach and initially puts them everywhere on the wafer. “We put the tubes everywhere and then get rid of the ones in the wrong places,” Schmergel told us. Using lithography and etching, Nantero gets rid of the excess tubes and the remaining ones form a usable pattern.
Schmergel told us that its memory chips are in a pre-production phase and should be out sometime next year. He adds, “We are already testing them at room temperature.” However, memory chips are just the beginning and Schmergel already has his sights set on other components. Cache memory and processors are a fair game for CNT replacements. “After memory, we will be looking at doing some of the logic functions of the processor. But cache memory will probably happen earlier and can be embedded right away,” says Schmergel.
Of course the golden question is how much will these memory modules cost? Schmergel couldn’t give a price, but told us that the modules will sell for a “comparable amount” and that prospective buyers may pay a “little bit more” for an instant on machine. Considering the fact that CNT memory is likely to offer more capacity than today’s memory modules, the absolute price of one module, however, could be clearly higher than what memory devices go for today. “I hope that people will see the value in a machine that boots up instantly, versus a computer that takes five minutes to turn on,” he said.