Pushing The Boundaries of Data Storage in the Information Age

Every time you access the Internet, hit "send," trade a stock online, use an ATM or watch a Hollywood blockbuster movie, you create, access and share tremendous amounts of digital information. But what if you woke up one day and couldn't do any of it?

Keeping our networked, digital world up and running depends on storing, accessing and managing tons of data that is multiplying and growing dramatically every day. Where does it all come from? Where does it all go? And what will make sure I can continue enjoying my digital lifestyle? The answer is storage technology, like that found in disc drives. The ability for storage technology to continue its rapid pace of advancement is critical for people around the globe to have the world's information at their fingertips.

The growth of storage in our Information Age has exploded largely because of the ability to continue to deliver it inexpensively. But current technology presents limits to how much information can be stored on a disc drive. This means that eventually people may no longer be able to get twice the capacity each year for the same price as the previous year. With storage demands rising, it is critical that technologists develop the technologies that will continue to allow affordable storage for everyone.

The ability to store a given amount of information on a disc drive is driven largely by a drive's areal density. Areal density refers to both the size and how closely spaced the information bits are on a disc drive. By increasing the areal density on discs through the process of making the information bits smaller and more closely spaced, more data can be put onto the discs, meaning fewer discs and parts can be used inside a disc drive. With current storage technologies, there is an areal density limitation and technologists are working on needed storage breakthroughs for the next millennium. This is critical when considering how much storage people have continued to demand and use.

During the past five years especially, the demand for magnetic storage has grown at a tremendous rate. Key areas such as the Internet as well as networks and databases that create and use information for business have fueled this growth. With the increased need for storage, technologists working in the field continue addressing the challenge of increasing disc drive capacity while also making them faster. The bottom line is that if new breakthrough technologies aren't successfully implemented that can keep up with storage demands while overcoming areal density limitations; an inherent slowdown of information can occur that could inhibit businesses and people throughout the world. Additionally, issues such as much greater storage costs as well as capacity limitations are a part of this scenario. Given the demand and need for electronic information in our digital world, it is critical that this not happen.

Facts About Storage Use

Before examining the different methods that technologists are using to solve areal density challenges, it is important to note and appreciate the amount of magnetic storage people are using each year to produce and store digital content. According to the October 2000 University of California-Berkeley study through the School of Information Management and Systems, 1,693,000 terabytes of information are produced and stored magnetically worldwide each year, with an expected annual growth rate of 55%. To put this in perspective, one single terabyte of information (or 1000 gigabytes) is equivalent to storing a stack of text documents that is more than sixteen times the height of the Empire State Building. Include the additional 1,692,999 terabytes of data and it becomes clear that the world is producing and storing a virtual myriad amount of magnetic data.

Several factors contribute to this demand for storage. Internet traffic is approximately doubling each year, according to the recent 2001 report by Coffman and Odlyzko entitled, "Is there a Moore's Law for data traffic?" And ETForecasts discovered that home Internet use itself has quadrupled since 1995, going from 9 percent to 41.5 percent of all homes in less than 5 years. It was also Odlyzko in an earlier 2000 report, "Content is not King" who wrote that communication such as e-mail was "the killer app" that required an enormous amount of storage capacity, not web content. In fact, the UC Berkley team also affirmed this by reporting that approximately 610 billion e-mails are sent per year.

When moving outside of the Internet arena, storage used for business networks and databases is also expected to grow rapidly. In fact, International Data Corporation estimated that implementations such as Network Attached Storage (NAS) and Storage Area Networks will both grow to a combined revenue of $18.6 billion by 2003. Additionally, storage services worldwide are expected to top $40 billion.

Pushing the Technology Boundaries - The Technical Details

Disc drives at their most basic level work on the same mechanical principles as media such as compact discs or even records, however, magnetic disc drives can write and read information much more quickly than compact discs (or records for that matter!). The specific data is placed on a rotating platter and information is then read or written via a head that moves across the platter as it spins. Records do this in an analog fashion where the disc's grooves pick up various vibrations that then translate to audio signals, and compact discs use a laser to pick up and write information optically.

In a magnetic disc drive, however, digital information (expressed as combinations of "0's" and "1's") is written on tiny magnetic bits (which themselves are made up of many even smaller grains). When a bit is written, a magnetic field produced by the disc drive's head orients the bit's magnetization in a particular direction, corresponding to either a 0 or 1. The magnetism in the head in essence "flips" the magnetization in the bit between two stable orientations. In currently produced hard disc drives, longitudinal recording is used. In longitudinal recording, the magnetization in the bits is flipped between lying parallel and anti-parallel to the direction in which the head is moving relative to the disc.

Increasing areal densities within disc drives is no small task. For the past couple of years, technologists have been increasing areal densities in longitudinal recording at a rate in excess of 100% per year. But it is becoming more challenging to increase areal densities, and this rate is expected to eventually slow until new magnetic recording methods are developed.

To continue pushing areal densities in longitudinal recording and increase overall storage capacity, the data bits must be made smaller and put closer together. However, there are limits to how small the bits may be made. If the bit becomes too small, the magnetic energy holding the bit in place may become so small that thermal energy may cause it to demagnetize over time. This phenomenon is known as superparamagnetism. To avoid superparamagnetic effects, disc media manufacturers have been increasing the coercivity (the "field" required to write a bit) of the disc. However, the fields that can be applied are limited by the magnetic materials from which the head is made, and these limits are being approached.

According to Dr. Mark Kryder, senior vice president at Seagate Research, longitudinal recording still has time left before reaching the superparamagnetic limit. "We expect today's longitudinal recording methods to take us beyond 100 gigabits per square inch in density. A great challenge however is maintaining a strong signal-to-noise ratio for the bits recorded on the media. When the bit size is reduced, the signal-to-noise ratio is decreased, making the bits more difficult to detect, as well as more difficult to keep stable."

Perpendicular recording is widely seen as the next method of recording that will be adopted to help push areal densities further. Dr. Kryder estimates that the switch to perpendicular recording will occur sometime between 100 and 200 gigabits per square inch areal density. In perpendicular recording, the magnetization of the disc, instead of lying in the disc's plane as it does in longitudinal recording, stands on end perpendicular to the plane of the disc. The bits are then represented as regions of upward or downward directed magnetization (corresponding to the 1's and 0's of the digital data).

Perpendicular recording enables one to record bits at a higher density than longitudinal recording, because it can produce higher magnetic fields in the recording medium. In perpendicular recording the media can be deposited on a soft magnetic underlayer that effectively produces an image of the recording head and approximately doubles the recording field.

Even though perpendicular recording will take magnetic recording technology much further than the current longitudinal methods, superparamagnetic effects still exist at some point, though it is difficult to predict exactly when this will occur.

"At this time, we estimate that perpendicular recording methods may take us all the way to one terabit per square inch," Dr. Kryder continued. "When that level is reached, a single 3.5 inch disc will store over one terabyte of information."

While that amount of storage is a significant advance beyond that of storage capacity available in a single drive today, when put into perspective with the best estimates and forecasts of our current and future storage requirements, the need for technologists to continue to forge ahead beyond that figure is clear. The UC Berkeley study reported that the world produces between 1 and 2 exabytes (one exabyte is the equivalent of one billion gigabytes) of information each year in total, comprising all magnetic, paper, film, and optical data. In addition to that sum, it is conceivable that eventually much of the older media such as those produced on film and paper may also make its way to magnetic data translation, increasing the overall total figure further.

Further Into the Future

Beyond longitudinal and perpendicular recording, technologists are already beginning to explore other possible methods of recording data. Still many years away, optically-assisted (also known as thermally-assisted) magnetic recording, or a type of patterned or self-ordered magnetic array are viewed as possible candidates for storing the world's information.

Optically-assisted recording involves producing a hot spot (commonly with a laser) on the media, while data is simultaneously written magnetically. The net effect is that when the media is heated, the coercivity or field required to write on the media is reduced, making it possible to write high-coercivity media (which as explained above have higher stability against superparagmagnetism), in spite of the limited fields that can be produced by recording heads.

Technologists such as Seagate Research's Dr. Dieter Weller are also working on patterned media, or what is also being called self-ordered magnetic arrays (SOMA). "A typical bit of information is made up of about 100 grains of material. We are working to convert each grain to a unique bit of information. As a result, a large gain in bit density would be achieved," said Dr.Weller.

Dr. Weller added that Seagate Research is working on ways to make the grains "order" in a regular array so that the bits can be read and written and so that good thermal stability can be achieved. Weller believes that iron platinum (FePt) is the best material to use along with a careful balance of other chemicals.

Probe storage may be one of the more unusual methods of recording proposed since it doesn't involve the use of discs at all. Rather, probe storage technology could be implemented in something the size of a typical semiconductor chip. It works like a scanning microscope, except there is an array of these microscopes or probes that read and write the data. Each probe addresses an array of bits of information, and the probes write and read in parallel. Several media candidates are under consideration, including magnetic media, and, unlike typical silicon chips, they won't lose memory once power is turned off. It is estimated that about 10 gigabytes of information will be able to be stored on a centimeter-sized chip.

While probe storage offers interesting possibilities, Dr. Kryder doesn't view it as a replacement for disc drives. Rather, he envisions probe storage chips working in a large number of consumer electronic devices that require a solid state, low-power storage device with moderate capacity. He even envisions them being put into disc drives to act as a memory buffer to allow faster access to information than the drive alone can provide.

The Information Age Continues

With computers firmly entrenched in our world, the need for more storage has never been greater. While it is difficult to truly estimate how much storage we will need and use in the future, there is no debate that the figure is astronomical. At no other point in the history of mankind has there been such a thirst for so much information. As a result, in this Information Age achieving the goal of allowing the average person access to all recorded information ever produced, is a significant, yet important one. It is information after all, that will ultimately help move us into newer and greater eras of enlightenment and discovery.



Industry's Best Power Efficiency Offers Benefits for IT and CE Applications

SAN JOSE, Calif. - July 6, 2005 - Hitachi Global Storage Technologies is bringing to market the industry's highest-performing*, yet most power-efficient hard drive for the mainstream notebook and consumer electronic segments. In addition, the Hitachi Travelstar 4K120 is the first 2.5-inch hard drive to provide customers with an option for the AV Streaming Command Set - or Smooth Stream(tm) as introduced by Hitachi - which enhances audio/video streaming capability in digital entertainment devices, such as digital video recorders (DVR). The combination of these attributes makes Hitachi's 120-gigabyte** (GB) Travelstar 4K120 the technology leader in the 4200 RPM 2.5-inch hard drive space.

"While the 4K120 is primarily being used in the mainstream notebook segment, we've created a highly sophisticated hard drive that offers users the greatest value for their money for a range of applications," said Becky Smith, vice president, marketing, Hitachi Global Storage Technologies. "The list of leadership characteristics that the 4K120 has accumulated is representative of the commitment and expertise Hitachi brings to the 2.5-inch segment and our expansion into the consumer electronics space."

As an added benefit, the 4K120's low power-consumption also results in cooler operation and longer battery life in notebook systems, which could result in extended service life for both the hard drive and host product. In CE environments, the cooler-running hard drive can be used in a new category of smaller, entry-level DVRs intended for spaces such as bedrooms, where quieter operation is possible as fans are not required for cooling the host device.

Cool, Fast, Long-lasting

In the notebook space, the 4K120 out-performs all other 4200 RPM 2.5-inch hard drives based on published specifications for seek time, read/write functions and data transfer rates. While higher performance usually comes at the expense of power consumption, the 4K120 actually leads the industry in battery life due to the new Hitachi Voltage Efficiency Regulator Technology (HiVERT) in conjunction with other power management mechanisms. HiVERT works by reducing the power draw of key hard drive electrical components by 30 percent over the previous generation. In Hitachi's energy discharge test, the 4K120 shows between a 29- and 178-percent better power utilization than competitive 4200 RPM hard drives available on the market.

The 4K120's excellent power utilization directly correlates to a significant reduction in heat dissipation. With hard drives among the top three heat producers in laptop computers (behind the processor and graphics card), the 4K120's significantly lower heat dissipation will reduce the overall heat emission of notebooks for greater lap comfort. Thermal imaging tests conducted in Hitachi labs show a marked difference in heat emission between the Travelstar 4K120 and competitive hard drives in similar notebook operations

For Your Enjoyment

The 2.5-inch category is fast becoming a desirable form factor for CE manufacturers due to its smaller size and high capacity. DVR manufacturers, who typically use 3.5-inch drives for video storage, are now looking for a new hard drive to go into devices that are quieter and smaller. With its cool operation and new AV streaming capabilities, the Travelstar 4K120 is the first 2.5-inch hard drive to meet these needs, helping manufacturers to create a new category of fan-less DVRs that are "bedroom quiet." The Travelstar 4K120 continues the leadership established by Hitachi's Deskstar 3.5-inch product line by becoming the first 2.5-inch hard drive to offer the ATAPI/ATA-7 AV Streaming Command Set.

The 4K120 is also ideal for interactive game consoles, set-top boxes, digital jukeboxes and personal media player devices.

Product Availability

The Travelstar 4K120 is now shipping in volume to customers in 40-, 60-, 80-, 100- and 120-GB capacities. Availability in the channel is expected by August. The 4K120 is Hitachi's 30th-generation 2.5-inch product, which is based on the industry's most mature and stable platform for the category.

* based on available specifications
** 1 gigabyte equals one billion bytes

Technical Specifications
Travelstar 4K120

120/100/80/60/40 GB
9.5 mm in height
99/99/99/95/95 grams maximum weight
4200 rpm
7.1 ms average latency
98 billion bits per square inch maximum areal density
2/2/2/1/1glass disk platter(s)
4/4/3/2/2GMR recording head(s)
1000 G/1ms non-operating shock
300 G/2ms operating shock
11 ms average read time/13 ms average write time
0.65 W active idle
0.45W low-power idle
0.15W standby
100 MB/sec maximum interface transfer rate ATA-6 Ultra DMA mode-5

About Hitachi Global Storage Technologies

Hitachi Global Storage Technologies was founded in 2003 as a result of the strategic combination of Hitachi's and IBM's storage technology businesses. Hitachi GST is the industry's second largest hard disk drive manufacturer in revenue.

The company's goal is to enable users to fully engage in the digital lifestyle by providing access to large amounts of storage capacity in formats suitable for the office, on the road and in the home. The company offers customers worldwide a comprehensive range of storage products for desktop computers, high-performance servers and mobile devices. For more information on Hitachi Global Storage Technologies, please visit the company's Web site at

About Hitachi, Ltd.

Hitachi, Ltd., (NYSE: HIT), headquartered in Tokyo, Japan, is a leading global electronics company with approximately 347,000 employees worldwide. Fiscal 2004 (ended March 31, 2005) consolidated sales totaled 9,027.0 billion yen ($84.4 billion). The company offers a wide range of systems, products and services in market sectors including information systems, electronic devices, power and industrial systems, consumer products, materials and financial services. For more information on Hitachi, please visit the company's Website at


Over the last four years, a new generation of consumer devices has radically changed the way people accumulate, enjoy and store entertainment. At the heart of the latest consumer electronic devices is what Hitachi is affectionately calling the new "Bling" - hard disk drives. These incredible shrinking drives have been instrumental in driving the digital revolution and a series of announcements from Hitachi today will drive future developments:


Hitachi unveils terabyte DVD recorder

TOKYO, Japan (Reuters) -- Japan's Hitachi Ltd. on Wednesday unveiled the world's first hard disk drive/DVD recorder that can store one terabyte of data, or enough to record about 128 hours of high-definition digital broadcasting.

Hitachi, Japan's largest electronics conglomerate, is still a relatively small player in the DVD recorder market, trailing industry leaders Matsushita Industrial Co. Ltd., Sony Corp. and Toshiba Corp.

But it hopes its new line-up, which also includes models able to store 160 gigabytes, 250 gigabytes and 500 gigabytes of data, will help boost its market share and turn its loss-making DVD recorder business profitable in October-March, the second half of the business year.

"We entered the market last year and have only been able to grab about 3 percent of the market. It's been hard to earn a decent return on investment with such (low) volumes," Norio Ogimoto, general manager of Hitachi's storage media group, told a news conference.

"But we plan on being profitable with these new models given the volumes and prices we expect to see from them," he said.

Hitachi said the new models would be the first on the market able to simultaneously record two high-definition programs, and it hopes this will be a key selling point given the spread of terrestrial digital broadcasting in Japan.

The recorders will go on sale in Japan from next month. They are expected to retail from about 130,000 yen ($1,180) for the cheapest model to 230,000 yen for the one-terabyte recorder, which stores data on two 500 gigabyte hard disk drives.

One terabyte is equal to 1 trillion bytes of data. One gigabyte equals 1 billion bytes.

Hitachi said it did not have concrete plans for launching the products in overseas markets, explaining that consumers in Europe and the United States were not as keen on high-end recorders.

Japan accounts for more than half of the global DVD recorder market. DVD recorders have been slow to take off in other markets such as the United States, where TV set-top boxes with hard drives, such as those made by TiVo Inc., are popular.

MM Research Institute predicts that Japan's DVD recorder market will grow 26 percent to 5.6 million units in the current financial year to next March, up from 4.43 million in 2004/05.

Hitachi said it was aiming to grab 35 percent of the Japanese market for high-definition DVD recorders in the second half of this business year. High-definition recorders currently make up about 15 percent of the overall market, but that percentage is expected to grow strongly over the next several years.