IBM's 'pixie dust' breakthrough to quadruple disk drive density

May 20, 2001

IBM is first to ship products with 'magical' new material

San Jose, Calif., May 21, 2001 -- IBM today announced that it is using just a few atoms of "pixie dust" to push back the data storage industry's most formidable barrier.

The company is first to mass-produce computer hard disk drives using a revolutionary new type of magnetic coating that is eventually expected to quadruple the data density of current hard disk drive products -- a level previously thought to be impossible, but crucial to continue feeding the information-hungry Internet economy. For consumers, increased data density will help hasten the transition in home entertainment from passive analog technologies to interactive digital formats.

The key to IBM's new data storage breakthrough is a three-atom-thicklayer of the element ruthenium, a precious metal similar to platinum, sandwiched between two magnetic layers. That only a few atoms could have such a dramatic impact caused some IBM scientists to refer to the ruthenium layer informally as "pixie dust."

Known technically as "antiferromagnetically-coupled (AFC) media," the new multilayer coating is expected to permit hard disk drives to store 100 billion bits (gigabits) of data per square inch of disk area by 2003. AFC media is now shipping in IBM's Travelstar notebook hard disk drive products with data densities up to 25.7 gigabits per square inch. In time, IBM plans to implement AFC media across all of its disk drive product lines.

The increasing data densities enabled by AFC media are expected to simplify processes for storing consumers' rapidly growing volumes of digital data (music, photographs, presentations and video); accelerate an industry trend toward smaller disk-drive form factors that consume less energy; and stimulate the creation of new and more capable digital-media and data-intensive applications.

In the past decade, the data density for magnetic hard disk drives has increased at a phenomenal pace: doubling every 18 months and, since 1997, doubling every year, which is much faster than the vaunted Moore's Law for integrated circuits. But the designers knew they were accelerating toward a barrier that could suddenly halt further progress: When magnetic regions on the disk become too small, they cannot retain their magnetic orientations -- the data -- over the typical lifetime of the product. This is called the "superparamagnetic effect," and has long been predicted to appear when densities reached 20 to 40 billion bits (gigabits) per square inch, which is near the data density of current products.

"AFC media is the first dramatic change in disk drive design made to avoid the high-density data decay due to the superparamagnetic effect," said Currie Munce, who holds the dual positions of director, Advanced Hard Disk Drive Technology at IBM's Storage Technology Division and director, Storage Systems and Technology at IBM's Almaden Research Center. "Our deep understanding of the complex physical phenomena of how the AFC media works enabled us to be first in the industry to ship AFC media in products, and we're working to extend this technology to perform magnetic recording at 100 gigabits per square inch and beyond."

The 100-gigabit density milestone was once thought to be unattainable due to the superparamagnetic effect. A natural solution to this problem is to develop new magnetic alloys that resist more strongly any change in magnetic orientation. But recording data on such materials becomes increasingly difficult.

AFC media solves this problem. The ultra-thin ruthenium layer forces the adjacent layers to orient themselves magnetically in opposite directions. The opposing magnetic orientations make the entire multilayer structure appear much thinner than it actually is. Thus small, high-density bits can be written easily on AFC media, but they will retain their magnetization due to the media's overall thickness.

With AFC media, 100-gigabit data density could allow the following capacities within two years:

Desktop drives -- 400 gigabytes (GB) or the information in 400,000 books; Notebook drives -- 200 GB, equivalent to 42 DVDs or more than 300 CDs;IBM's one-inch Microdrive -- 6 GB or 13 hours of MPEG-4 compressed digital video (about eight complete movies) for handheld devices.

IBM is a pioneer in the research, development and manufacture of antiferromagnetically-coupled structures, which have remarkable properties due to the "spintronic" interactions between the materials' electrons and magnetic fields. In 1990, IBM scientists discovered that a thin layer of ruthenium atoms created the strongest anti-parallel coupling between adjacent ferromagnetic layers of any nonmagnetic spacer-layer element. The structure was used in in the first giant magnetoresistive read element for disk drives, which was introduced by IBM in 1997. GMR heads are now used in virtually all disk drives.
About IBM's Travelstar disk drives:

The following IBM Travelstar (2.5-inch-disk form factor) products announced on March 27 are shipping with AFC media:

Travelstar 48GH -- 48GByte capacity, 5,400 rpm; 21.7 gigabits/inch2 maximum areal density

Travelstar 30GN -- 30/20 GB, 4,200 rpm; 25.7/23.2 gigabits/inch2 maximum areal density

Travelstar 15GN -- 15/10/6 GB, 4,200 rpm; 25.7/21.2/21.2 gigabits/inch2 max. areal density

About IBM

IBM develops and manufactures the industry's most advanced information technologies, including computer systems, software, networking systems, storage devices and microelectronics. The IBM Storage Technology Division offers customers worldwide the most comprehensive range of industry-leading storage products available today. These storage solutions are offered through IBM, as well as a large network of IBM Business Partners and Original Equipment Manufacturers (OEMs). Additional information on the Travelstar can be found at or by calling 1-888-426-5214.

IBM developed the first commercial hard-disk drive in 1956 and has been the data storage industry's technology leader ever since. Last year, IBM received the National Medal of Technology, the highest honor the President can bestow on leading innovators, in recognition of its leadership in developing and commercializing data-storage technologies.

IBM Research is the world's largest information technology research organization, with more than 3,000 scientists and engineers at eight labs in six countries. IBM Research labs are located in Yorktown Heights, N.Y.; San Jose, Calif.; Austin, Tex.; Zurich, Switzerland; Haifa, Israel; Tokyo, Japan; Beijing, China, and Delhi, India. For more information, please visit

IBM Watson Research Center

Related Technology Articles from Brightsurf:

December issue SLAS Technology features 'advances in technology to address COVID-19'
The December issue of SLAS Technology is a special collection featuring the cover article, ''Advances in Technology to Address COVID-19'' by editors Edward Kai-Hua Chow, Ph.D., (National University of Singapore), Pak Kin Wong, Ph.D., (The Pennsylvania State University, PA, USA) and Xianting Ding, Ph.D., (Shanghai Jiao Tong University, Shanghai, China).

October issue SLAS Technology now available
The October issue of SLAS Technology features the cover article, 'Role of Digital Microfl-uidics in Enabling Access to Laboratory Automation and Making Biology Programmable' by Varun B.

Robot technology for everyone or only for the average person?
Robot technology is being used more and more in health rehabilitation and in working life.

Novel biomarker technology for cancer diagnostics
A new way of identifying cancer biomarkers has been developed by researchers at Lund University in Sweden.

Technology innovation for neurology
TU Graz researcher Francesco Greco has developed ultra-light tattoo electrodes that are hardly noticeable on the skin and make long-term measurements of brain activity cheaper and easier.

April's SLAS Technology is now available
April's Edition of SLAS Technology Features Cover Article, 'CURATE.AI: Optimizing Personalized Medicine with Artificial Intelligence'.

Technology in higher education: learning with it instead of from it
Technology has shifted the way that professors teach students in higher education.

Post-lithium technology
Next-generation batteries will probably see the replacement of lithium ions by more abundant and environmentally benign alkali metal or multivalent ions.

Rethinking the role of technology in the classroom
Introducing tablets and laptops to the classroom has certain educational virtues, according to Annahita Ball, an assistant professor in the University at Buffalo School of Social Work, but her research suggests that tech has its limitations as well.

The science and technology of FAST
The Five hundred-meter Aperture Spherical radio Telescope (FAST), located in a radio quiet zone, with the targets (e.g., radio pulsars and neutron stars, galactic and extragalactic 21-cm HI emission).

Read More: Technology News and Technology Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to