Featured Research

from universities, journals, and other organizations

Hard drives: A bit of progress

Date:
May 10, 2012
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
A modified approach to fabrication of magnetic memory elements may lead to a new generation of stable, ultra-high-capacity hard drives.

A magnetic film patterned into an array of dots (background) is known as a bit-patterned medium, and can store data at very high areal densities. Each dot requires a slightly different magnetic field to write or erase. Ranjbar and co-workers reduced this variation by adding a continuous layer underneath the dots, made of the same material as the dots themselves (green). By comparison, the traditional approach (yellow) had both a wider variation, and higher average switching fields.
Credit: Copyright A*STAR

A modified approach to fabrication of magnetic memory elements may lead to a new generation of stable, ultra-high-capacity hard drives.

Information in most computer memories is stored in the form of 'bits' represented by the polarization of tiny magnets on the surface of memory devices such as the computer's hard drive. The capacities of these devices have increased exponentially over the last 30 years, a feat made possible by progressively reducing the area taken up by the magnets storing the information. In modern machines, these magnets are so small that reducing their size any further risks creating unstable data, due to random flipping of the direction of polarization of the magnets at higher densities. Now, Mojtaba Ranjbar and colleagues at the A*STAR Data Storage Institute have honed a key technology, called bit-patterned media, to overcome this problem and allow data to be stored at previously unattainable densities.

Bit-patterned media technology replaces the continuous magnetic film traditionally used in hard drives with an array of small, patterned magnetic dots (see image), each of which stores a bit of data. By carefully designing the size and shape of these dots, data can be stored at very high densities without the instability that would be encountered if a continuous film were used.

Using bit-patterned media, however, is not without its own difficulties, chief among which is a problem known as 'switching field distribution', whereby the magnetic field required to write or erase data in each dot differs slightly and by an unknown amount. As a result, the magnetic field applied by a hard drive write head may be too small, or too large, resulting in data errors.

Previous work by other researchers sought to minimize the switching field distribution problem by covering all of the magnetic dots with a continuous magnetic film placed on top of the dots, which alters the magnetic interactions between individual dots. The approach called 'capped bit-patterned media' traditionally requires different magnetic materials for the dots and film, introducing additional fabrication complexity.

Ranjbar and co-workers used the same material for the film and dots, and positioned the dots above the film rather than below it. This approach allowed a particularly simple fabrication process, in which dots were etched in a controlled fashion, leaving a continuous, unetched film underneath and obviating the need for a separate deposition step to introduce a new magnetic material.

The researchers found that this simplified process successfully reduced switching field distribution, and also lowered the field strengths necessary for writing data. Ranjbar comments, "Combined with the ease of fabrication, this technology should prove useful in bit-patterned media for next-generation hard disk drives."


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Ranjbar, S. N. Piramanayagam, S. K. Wong, R. Sbiaa, T. C. Chong. Anomalous Hall effect measurements on capped bit-patterned media. Applied Physics Letters, 2011; 99 (14): 142503 DOI: 10.1063/1.3645634

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Hard drives: A bit of progress." ScienceDaily. ScienceDaily, 10 May 2012. <www.sciencedaily.com/releases/2012/05/120510095620.htm>.
The Agency for Science, Technology and Research (A*STAR). (2012, May 10). Hard drives: A bit of progress. ScienceDaily. Retrieved August 29, 2014 from www.sciencedaily.com/releases/2012/05/120510095620.htm
The Agency for Science, Technology and Research (A*STAR). "Hard drives: A bit of progress." ScienceDaily. www.sciencedaily.com/releases/2012/05/120510095620.htm (accessed August 29, 2014).

Share This




More Computers & Math News

Friday, August 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

JPMorgan Chase Confirms Possible Cyber Attack

JPMorgan Chase Confirms Possible Cyber Attack

Reuters - US Online Video (Aug. 28, 2014) Attackers stole checking and savings account information and lots of other data from JPMorgan Chase, according to the New York Times. Other banks are believed to be victims as well. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Spend 2 Minutes Watching This Smartwatch Roundup

Spend 2 Minutes Watching This Smartwatch Roundup

Newsy (Aug. 28, 2014) LG announces a round-faced smartwatch, Samsung adds 3G connectivity to its latest wearable, and Apple will reportedly announce the iWatch on Sept. 9. Video provided by Newsy
Powered by NewsLook.com
Google Reveals Drone Delivery Program, 'Project Wing'

Google Reveals Drone Delivery Program, 'Project Wing'

Newsy (Aug. 28, 2014) Google has been developing a drone delivery system of its own, and it hopes to revolutionize how people view possessions with it. Video provided by Newsy
Powered by NewsLook.com
Why Apple Might Add Mobile Payment Options To iPhone 6

Why Apple Might Add Mobile Payment Options To iPhone 6

Newsy (Aug. 28, 2014) A report by Wired suggests Apple's next iPhone will feature a mobile payment system and near-field communication. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins