Hitachi announces indestructible memory
Hitachi has developed a nearly indestructible medium for storing digital information, using quartz glass that has the potential for practical use in any commercial digital system.
Magnetic storage – everything from tape to hard drives to semiconductor memory – can start to degrade after only a few years. CD technology can last significantly longer – tens or maybe hundreds of years. But CDs (and similar successor formats) still must be handled with care to avoid scratches, warping and other damage.
Hitachi’s quartz-based memory medium, on the other hand, is of course waterproof and can endure extreme temperatures and other hostile conditions, with the potential to last a few hundred million years, the company calculates.
The quartz substrate is written using a method analogous to the way CDs are written – with a laser that creates a series of physical dots that can be read with an ordinary optical microscope.
The prototype storage device has four layers and is approximately 0.8 inches square and just 2 millimeters (roughly 0.08 inches).
With its current production process, and with information stored on all four layers, the medium stores about 40 MB per square inch, or roughly equivalent to the storage density of a CD-ROM. Storage density should be improved, however. One method would be to simply add more glass layers.
Hitachi first developed the quartz medium in 2009, but lacking a means of rapid writing, it was still then just a lab curiosity. The significance of the recent announcement is that Hitachi believes it has developed a means of writing data rapid enough for the technology to be a viable option for commercial applications, possibly within three years.
"The volume of data being created every day is exploding, but in terms of keeping it for later generations, we haven't necessarily improved since the days we inscribed things on stones," Hitachi researcher Kazuyoshi Torii said.