Toshiba Corporation has unvieled what it claims are the world’s first hard disk drives (HDD) based on perpendicular recording, a technology that boosts the capacity of a single 1.8-inch hard-disk platter to 40 gigabytes.
Toshiba has brought the new technology to two high capacity drives: the MK4007GAL HDD packs 40GB into a drive only five millimeters thick, while the MK8007GAH achieves a capacity of 80GB – the largest capacity yet achieved in the 1.8-inch form factor.
Toshiba plans to start mass production of the 40GB and 80GB drives in the first and second quarters, respectively, of the fiscal year starting April 1, 2005.
For the new drives, Toshiba developed a new magnetic disk structured to support perpendicular recording, a new high performance perpendicular magnetic head, and disk and head integration technology that maximizes their combined performance.
Conventional longitudinal recording stores data on a magnetic disk as microscopic magnet bits aligned in plane. Although advances in magnetic coatings continue to improve data recording densities on HDD, the magnetic bits repulse each other due to in-plane alignment. Squeezing more bits on to a disk will eventually reach a point where crowding degrades recorded bit quality. This places fast-approaching limits on storage capacities.
By standing the magnetic bits on end, perpendicular recording reinforces magnetic coupling between neighbouring bits, achieving stable higher recording densities and improved storage capacity.
Toshiba’s new HDDs achieve the highest areal density yet reported, 206 megabits per square millimeter (133 gigabits per square inch). The 40GB platter capacity is 33% more than that of Toshiba’s conventional HDD.
Toshiba will also apply the new technology to the 0.85-inch HDD that it announced in January this year, a move that will push capacity to 6 to 8GB per platter.