Tokyo, April 6, 2000 -- Fujitsu has succeeded in developing a new
type of recording media, called Layer Exchange Interaction Stabilized, which has the potential to achieve three times the
density of the current theoretical limit governed by thermal
fluctuation of magnetization. The new media technology will be used
to expand the capacity of hard-disk drives (HDDs) for information
storage devices for computers and home information electronics
products. Using the new media technology together with a newly
developed head, Fujitsu has already demonstrated a recording density
of 56Gb/sq. inch -- the world's best performance as of today.
With this density, a 3.5-inch HDD containing two disks could store
about 30 movies in DVD-quality video. Moreover, when used together
with high-output heads, the new media technology has the potential
to achieve a recording density of 300Gb/sq.in.
The details of the new media technology will be announced at the
International Magnetics Conference in Toronto, Canada, which will
take place from April 9. A portion of this technology is based on
research sponsored by ASET (the Association of Super-Advanced
Electronics Technologies).
Development Background
The growing use of the Internet and digital cameras has increased
the need for recording and storage of sound and image data, even on
home-use PCs. A compressed still image requires several tens of
kilobytes of storage capacity, and a one-minute video requires 30
megabytes (current television transmission-standard compressed data).
In recent years, average HDD capacity has been increasing annually
by 1.6 - 2 times. At such a rate, products with 100Gb/sq.in.
recording density might be expected to appear by 2003.
However, thermal decay, which makes recorded information unstable
or ultimately causes loss of information, has been a bottleneck in
the development of higher-density technology. Fujitsu has addressed
this issue by developing the new Layer Exchange Interaction Stabilized media.
Technology Features
- The Fujitsu development team was able to reduce information
degradation resulting from the media's thermal decay by adding a
multi-layer stabilizing layer under the recording layer. The
stabilizing layer does not affect information output, and by
firmly coupling magnetically with the recording layer (anti-
ferromagnetic coupling) it stabilizes recording signals from
degradation, even at higher recording density.
- As a result of this technology, degradation of recorded
information by thermal decay can be reduced to one fifth of
current levels.
- With a prototype media using this technology and specular GMR
(giant-magneto-resistive) head now under development, Fujitsu
researchers have demonstrated 56 Gb/sq.in. recording density - a
world record. This level of density is equivalent to 78 gigabytes
(627 Gbits) on a single 3.5 disk.
The density limit imposed by thermal decay in existing media has
been estimated at 100 Gb/sq.in. Since media utilizing this new
technology is able to accommodate three times more magnetic energy
than the present media, it has potential to realize recording
density of 300 Gb/sq.inch when combined with a high-output head,
such as a TMR (Tunneling Magneto-Resistive) head.
About Fujitsu Limited
Fujitsu Limited (TSE: 6702) is a leading provider of comprehensive
information technology and network solutions for the global
marketplace. Comprising over 500 group companies and affiliates
worldwide -- including ICL, Amdahl and DMR Consulting Group -- the
Fujitsu Group had consolidated revenues of 5.24 trillion yen
($43.3 billion) in the fiscal year ended March 31, 1999. With world-
class hardware and software technology in computers,
telecommunications and microelectronics, and a corps of 55,000
systems and services experts around the world, Fujitsu is uniquely
positioned to harness the power of the network to help its customers
succeed. Altogether, the Fujitsu Group has 188,000 employees and
operations in over 100 countries.
Homepage: http://www.fujitsu.com/
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