08.19.2010

Toshiba to reveal breakthrough in hard drive areal density

Toshiba Corp. has successfully flown a recording head over a track on a disk that packs 2.5 terabits of data per square inch, five times the density of today's hard disks.

The company has been developing bit-patterned media (BPM), a technique to make smaller collections of the grains used to record the magnetic charge for each bit and lay them out precisely on the

hard drive

, with an insulating ring around them to make them hold their magnetic charge more reliably. Toshiba has achieved, it says, a 2.5Tbit/in2 areal density, using magnetic dots 17nm in size, but has only managed to detect tracks on the prototype media, and is

not yet being able

 to read or write individual bits. This points to a read/write head technology problem.

The

read/write head

 has to detect and follow tracks and then read and write the bits in the tracks. There needs to be a head servo pattern for this as well as a data bit pattern. Toshiba says its demonstration of track detecting and following on a BPM disk is a world first and a breakthrough.

Three of the largest hard drive makers recently agreed to form an alliance to define an industry road map and coordinate research toward its goals. But even the members of that group say it is still unclear whether it will back patterned media or one of several approaches based on heat- or energy-assisted magnetic recording.

"In our labs, we are evaluating both and there are potential technical hurdles with both solutions, but with this development it looks like bit pattern media is a strong contender," said Maciek Brzeski, vice president of marketing for Toshiba's storage group.

The news was disclosed at the Magnetic Recording Conference in San Diego. Toshiba's highest areal density in a shipping dive is 541Gbit/in2 in its MK7559GSXP 2.5-inch hard disk drive. A quadrupling of areal density would take its capacity up from 750GB to 3TB. An equivalent jump in 3.5-inch hard drive capacity would see a leap to an 8TB drive.

It suggests it could get the dot size down to 10nm and the areal density doubled to 5Tbit/in2. The company thinks that it might be able to ship a BPM hard drives in 2013.