Optical Disc Storage Technology (Archived Report)

PDF version of this report
You must have Adobe Acrobat reader to view, save, or print PDF files. The reader
is available for free

Optical Disc Storage Technology

by Lynn Greiner

Docid: 00011050

Publication Date: 1407

Report Type: TUTORIAL


Capable of storing large quantities of data including text, images, sound,
and even full-motion video, optical storage systems span the home and business
market, scaling from personal computers to enterprise applications. The optical
storage world, however, is in a state of flux. The capacity of the disc, its ability to be
written to, and the speed with which the data can be accessed are the main selling
points for any system, whether based on DVD, Blu-ray, or other options on the
horizon. This report describes optical disc storage technology, alternative forms of optical storage, and the advanced technologies
being developed.

Report Contents:

Executive Summary

[return to top of this report]

Originating in the early 1980s, optical storage systems, which use lasers
to read and write digital data, experienced a growth spurt
following the development of DVDs. Fueled
by the needs of both the computer and entertainment industries, the CD, or
compact disc, went from being a static data delivery device to an
active storage system, designed to complement or, in some cases, displace
comparable magnetic media.

The CD drive is no longer the most popular
storage device for new computers. Pushed by the recording and computing
industries, and by users’ demand for higher capacity media, the DVD, or digital
versatile disc, is now firmly in the leading position. While a CD has a capacity of 650 MB, a
DVD can record up to 17 GB of digital audio, video, and computer data.

need for additional storage, particularly for archives, means that the optical storage market continues to
evolve. The next generation of disc storage to hit the market were the Blu-ray Disc, which gained more acceptance in Japan and the rest
of the Pacific Rim, and HD-DVD, which had the support of the major movie studios
that saw it as a replacement for the standard DVD player. The first HD-DVD computer drive from Toshiba hit the market
with the Qosmio G35-AV650 PC, and the first movie titles from Warner Home
Entertainment were introduced as well. Blu-ray hit the market with
Twentieth-Century Fox, Sony, Lionsgate Home Entertainment, and Walt Disney
Studios being among the first companies to release Blu-ray movies.
In addition, Sony shipped the first Blu-ray
equipped notebook, the Vaio VGN-AR70B; Philips quickly followed with its own Blu-ray
drive; and many gaming system vendors have long since adopted the technology, with
Microsoft a holdout until it included Blu-ray with the XBox One release in late

February 2008, the format battle came to an end when Toshiba
announced the end of its efforts to promote and develop HD-DVD.


[return to top of this report]

Data is recorded on optical discs when a laser device burns microscopic spots
or pits in the reflective layer of a spiral track. Binary information is encoded
by the length of these spots and the spaces between them. Optical data is read
and interpreted by a low-power laser beam, which is emitted from a detector in
the optical head of a disc player or reader.

Capable of storing large quantities of data, including text, images, sound,
even full-motion video, optical storage systems span the home and business
market, scaling from personal computers to large enterprise applications.

Within organizations, optical storage systems are incorporated as
part of an HSM, or Hierarchical Storage Management, scheme. Slower and more
expensive than magnetic discs but faster and more accessible than magnetic tape,
optical discs permit the retention of massive amounts of business data in an
on-line or near on-line form. Frequently, an automatic optical disc
changer, or optical jukebox, is employed. These devices can hold up to several
hundred discs, each available through one or more of the unit’s disc drives.

While the first optical discs came in large (12- or 14-inch) form factors and
were used primarily for data archiving, optical storage made a big splash
commercially with the introduction in the early 1980s of the CD-ROM, or
compact disc read-only memory. While the CD-ROM drive, which at one time was nearly ubiquitous,
has almost faded away, the DVD has become the de facto storage media for new
computers and has been the media of choice for movies and music for some time. 

that a single higher density format has taken over, it is expected that the DVD
will eventually become obsolete, as have the many formats before it. This will not happen quickly
due to the number of DVD players on the market, the higher
price of Blu-ray disks (although device prices have plummeted), and the fact that consumers also
need to upgrade their televisions to take advantage of the improved
video offered by Blu-ray. Currently, Blu-ray commands less than a quarter of the

Current View

[return to top of this report]

During 2001, four industry leaders – HP (Compaq),
Sony, Microsoft, and Philips Electronics – finalized a specification for native
support of compact disc-rewritable (CD-RW) drives in PC operating systems. The specification, known as "Mount Rainier,"
featured drag-and-drop CD
writing and dynamic disc formatting, which, when implemented by OS developers, made using CDs as easy as using floppy discs. CD-RW has moved into the
market quickly enough that few vendors even began producing an earlier writeable
CD format, called CD-R, or CD-Recordable.

While at one time, computers did not
natively support CD-ROM drives, it rapidly became the de facto standard drive on
all new computers. Desktop computers now typically come with a choice of
multimedia drive (many laptops, however, dispense with optical drives entirely).
Users can choose among CD-ROM, CD-RW, DVD, CD-RW/DVD combo, writeable
DVD, or Blu-ray. Some home and business computers come with two drives and use a combination of
media types. New formats now appear as options.

Surprisingly, it
was the
home user who drove the demand for the CD-RW due to the popularity of
downloading music and music files that require a CD burner to move them to a
portable format. DVD acceptance was also driven by the home market. The
extra storage capacity is useful in data-intensive pursuits such as gaming and
movies. DVD drives that play movies or music are becoming more widespread when
connected to TVs, which also increases its desirability on the desktop.

Businesses did not ignore the storage capacities of the DVD or the capabilities of the
CD-RW, but increasing file sizes and dropping hard drive costs have
pushed them to the sidelines,
especially if there is some form of network attached or storage area network
(SAN) storage already in place. Removable media is still useful,
however, when businesses need to send data to customers or suppliers.
However, today that media is frequently a USB flash drive, now that
they can hold up to 1 TB. Alternatively, companies make use of cloud services
for data transfers, eliminating removable media from the equation.

The market for
Blu-ray discs is also being driven by the consumer market, with the release of
more titles every month; serious home entertainment buffs will be looking for
players to take advantage of the extra storage capability. Studios are able to
include more extra material on the Blu-ray discs, making a higher price point
possible. However this higher price point, coupled with the need for higher
definition televisions to properly view the content,
have so far held back mass adoption. Gaming systems are increasingly
including Blu-ray drives.

Sony has released various optical disc media for archive storage that is
compatible with the its ODSD55U drive unit, released in the fall of 2012. This drive
is used with Sony’s future Optical Disc
Cartridges, which will be equipped with 12 discs within the cartridge. The
cassettes range from 300 GB to 1.5 TB of storage capacity. Once
installed on a PC, users can connect the ODS-D55U to a USB 3.0
interface. The purpose is to offer long term storage capabilities (its media is
rated for 50 years) that can
handle temperature and humidity changes as well as dust and be water resistant.
In addition, Sony has organized the Optical Disc Archive Advisory Group and will
extend participation to media and entertainment companies to help add new video
image archiving products. 

Mobile Backup. Since even a small notebook computer
comes equipped with a
60-GB or larger hard
drive, moving data to and from these devices, including backup and recovery, can
be a major problem. As a consequence, many manufacturers used to offer a
CD-RW or a combination DVD/CD-RW drive as a built-in or add-on component,
however many now dispense with optical media to minimize size and weight.
Instead, users increasingly use cloud-based services for backup and data
transfer. Some laptops do still offer DVD writers, however they are scarce, and
the drive is often an extra-cost option.

For older-model notebooks, there are a number of third-party external units,
from providers like Micro Solutions, Acer America, HP, and TEAC America.

Optical Disc Storage Products

The various types of optical disc storage are outlined below.

CD-Recordable Technology. CD-Recordable, or CD-R, technology was first introduced in 1988. Initially
intended as a product for prototyping commercial CDs and CD-ROMs, CD-R has
been embraced by both business and consumer customers, providing a reliable
vehicle for system backup and archiving, as well as file sharing and
publishing. Each disc can store about 650 MB of data (the equivalent of 20
four-drawer file cabinets), or 74 minutes of CD or VHS quality audio or video.

A CD-R disc possesses a special dye recording layer that permits
information to be written irreversibly. Such write-once recordings, often
referred to as WORM, have an extremely long read
life, between 70 and 200 years, perfect for archiving or for sensitive
applications that demand an audit trail. Also, unlike magnetic media, an
optical disc cannot be inadvertently – or intentionally – erased through
exposure to a magnetic field.

Derived from CD audio technology, there are two basic types of CD-ROMs:

  • Standard, or non-recordable, CD-ROMs, used for publishing software, plus
    distributing large data bases and directories.
  • Non-Standard, or recordable, CD-ROMs.

CD-Rewritable Technology. CD-rewritable, or CD-RW, technology debuted in 1996. Complementing CD-R
technology, CD-RW is designed for file backup and other reusable storage

A CD-RW disc possesses a special phase-change metal recording layer that
permits information to be written and re-written, up to 1000 times. While not as
data durable as a CD-R disc, the effective read life of a CD-RW disc is at least
30 years.

DVD. Advances in digital data storage and laser technology led to the development
in 1997 of DVD discs. While DVDs are similar to CDs (at least in appearance),
they can hold far more data. A silvery platter 120 mm in diameter, a DVD can
record information on both sides, storing up to 17 GB of digital audio, video,
or just plain textual data.

This increased storage capacity is accomplished by using both sides of the
media and by storing two layers of data on each side. A single layer DVD disc
holds 4.7 GB of data; a double sided dual layer disc up to 17 GB.

Owing to their enormous capacity, DVD discs promise an even wider assortment
of applications, including document imaging, records retention, desktop
publishing, computer-aided design and manufacturing, and video production and

Just like CDs, DVDs are available in multiple flavors and textures. Table 1
describes the types of DVD’s on the market and their storage

Table 1. DVD Formats
DVD Type Capacity Description
DVD-R 4.7 GB Similar to CD-R, customers can
write only once to this disc.
DVD+R 4.7 GB Similar to CD+R
DVD-RW 4.7 GB per side Similar to CD-RW, this disc
can be re-written up to approximately 1,000 times.
DVD+RW 4.7 GB per side Similar to CD+RW, this disc
can be re-written up to approximately 1,000 times.
DVD-RAM 4.7 GB per side A virtual "hard disc," this disc can be re-written more than 100,000 times.
DVD+R DL 8.5 GB Single-sided, dual
layer, write once.
DVD-10 9.4 GB The disk is written on both sides and usually must be
manually flipped.
DVD (DVD-18)
17 GB (if two layers on both
sides of the disc are utilized)
Used for viewing films and
other visual entertainment.

DVD-RAM Technology. Rewritable DVD-RAM uses a land/groove structure and phase change material to
record data. The land/groove combination forms a continuous spiral track, with
data recorded alternately on land and groove. Phase change material is used as
the recording medium. This material can assume two distinct states, crystalline
or amorphous. Initially in a highly-reflective crystalline state, a portion of
the phase change material is transformed through a process of rapid heating and
cooling into a lower-reflective amorphous form. This area of low reflectivity
represents a recorded data mark.

DVD-RAM media is designed to support rewriting of data more than 100,000
times during the lifetime of a disc. This is achieved by implementing two
methods for randomizing the location and polarity of recordable data. DVD-RAMs
are expensive and are not offered by all vendors.

DVD has clung to its status as the kingpin in the optical storage
market despite new technologies rolling off the drawing board. A
case in point: in April 2005, the leaders of the two new optical camps, Blu-ray’s Sony, and HD-DVD’s
Toshiba, began talks about trying to merge the two formats so that customers,
who had revealed their dissatisfaction with two competing formats, would not
have to choose between two, thus hurting the sales of both. The talks fell
apart, and the two electronic giants decided to go to market with two
incompatible formats (Blu-ray discs will not play on HD-DVD players, and vice
versa). Through it all, standard DVDs continued to outsell both

The battle between the somewhat incompatible Blu-ray and HD-DVD formats is
long over, with the victor being Blu-ray. It had threatened to be similar to the Beta and VHS battle for the VCR
market, and had inhibited the adoption of either format. There are, however,
still other formats on the horizon. Not all of the
them will thrive, and some may never get off the drawing board.

Blu-ray Disc.

The Blu-Ray disc technology uses a 405-nanometer blue laser, and can potentially
store up
to 25 GB of data on one side or 50 GB on two sides. Targeted at video storage, the
five-inch Blu-ray Discs employ blue lasers,
which have a shorter wavelength. Companies involved in the Blu-ray Disc development included Hitachi,
JVC, Panasonic, Philips, Pioneer, Sony, Zenith, Sharp, LG Electronics, Mitsubishi, and Samsung.
Although the technology is mainly
focused on high-definition television, the industry has developed BD-ROM for
pre-recorded discs, BD-R for recordable disks, and BD-RE for rewritable discs.
BD+ offers content protection for digital rights management. The
Blu-ray Disc Association approved Version 2.0 of the rewritable format and is
working on version 1.1 of the recordable and read-only formats; it
also is touting the fact that Blu-ray players can play standard DVDs. Most
vendors offer desktop computers with Blu-ray drives; Sony includes Blu-ray in its
Playstation 3. In December
2008, Pioneer announced a 400 GB, 16 layer disc that’s compatible with
existing players. It expected readers to be available in 2009 -2010,
and writeable discs between 2010 and 2013, and it hoped to have a 1 TB
model by 2013, although there have been no
further published developments since the initial announcement, which suggests
that this technology is dead.

In January 2010 Sony and Panasonic announced plans to increase Blu-ray
disk capacity from 25 to 33.4 GB using technology known as Maximum
Likelihood Sequence Estimation (i-MLSE), which should be readable by
current Blu-ray players following a firmware upgrade. Sony plans to
propose that i-MLSE be adopted as a standard. In April 2010, two new
formats emerged: BDXL, a high-capacity recordable and rewriteable
format offering up to 128 GB, and IH-BD, Intra-Hybrid discs that are
not compatible with existing players.

In the first few months of 2010, Panasonic, Sony and Denon each
announced a 3D Blu-ray player, now that 3D films have entered the
market; 3D has now faded from the scene. LG and Samsung have since also announced products.
In 2013, the Blu-ray Disc Association announced the creation of a task force to
study an extension to the Blu-ray standard to support 4K Ultra HD video.


Toshiba and NEC developed the Advanced Optical Disc technology, now known as HD-DVD,
and had
proposed the standard to the DVD Forum, a consortium of 200 companies. The
proposed HD-DVD format as submitted to the DVD Forum included two-sided 30-GB or a
one-sided, 15-GB format. There were also a one-sided, read-only 15-GB and a
two-sided, read-only 30-GB discs. The HD-DVD was based on a 405-nanometer-wavelength blue laser and
store up to 15 GB of data on one side of a disc, which is about the  same size as a
conventional DVD disc. In December 2004, Toshiba introduced its rewritable
that it developed in conjunction with Memory Tech. The disc was the same size as a CD or
DVD and can store up to 30 GB of data. 

Toshiba began shipping recordable HD-DVD-Rs
and notebook drives. Other members of the HD-DVD consortium included
Sanyo and Memory Tech. However, in January 2008, the movie industry
announced it would support Blu-ray, so in February 2008, Toshiba
capitulated and has ceased development, manufacture, and sales of HD-DVD.

Ultra Density Optical (UDO). Used in
professional archiving products, these WORM devices succeed the old
magneto-optical (MO) drives. Currently available in UDO1, with a
capacity of 30 GB, and UDO2, with a 60 GB capacity, the technology
roadmap includes disks with 120 GB and 240 GB. UDO2 includes 256 bit
AES encryption. Vendors say that the technology offers three times the
data capacity at 84 percent less cost than MO. Although the primary
vendor of UDO, Plasmon, ceased to exist in November 2008, Alliance
Storage Technologies Inc (ASTI) purchased its assets in January 2009 and
continues to manufacture and support Plasmon products, including UDO
drives and media.


[return to top of this report]

Storage vendors are developing radically new optical disc storage technologies with
more capacity, in an attempt to extend the lifespan of optical disc storage.
The Optical Archive Group, an alliance among disc and drive manufacturers, has
been formed to meet the needs of organizations such as governments, medical
institutions, financial institutions, museums, and libraries that must archive
digitized data, or digitize original documents.

Over the years, many organizations have attempted to grow the capacity and
utility of optical technologies, with varying success. One thing that is consistent when discussing the cutting-edge
technologies is that they all promise increased capacity.

100-GB Optical Disc.
Researchers at the National Taiwan University (NTU) developed a prototype
rewritable optical disc that can store 100 GB of information and is compatible
with existing CD and DVD technology. Unlike other recent advances in optical
storage that require the use of blue lasers, the 100-GB disc developed by the NTU
team works with the read-write heads found in CD and DVD players that employ red
lasers, which have a longer wavelength than blue lasers. Matsushita
has demonstrated a working version. Sharp has developed a disc that operates
with Blu-ray, and in October 2007, Hitachi announced a 100 GB Blu-ray
quad layer disk that is compatible with existing players.

Several vendors, including TDK and Hitachi, announced 8
layer Blu-ray 200-GB discs in 2006 and 2007, but after a flurry of activity,
went silent on the subject. Currently TDK only markets 25GB Blu-ray discs.

300-GB Optical Disc. In July, 2013, Sony and Panasonic
announced that they had signed an agreement to jointly develop a next-generation
standard for optical discs used in archiving. They aim to develop a disc with at
least 300 GB capacity by the end of 2015. 

HD-VMD (Versatile
Multilayer Disc).
This technology, developed by the now defunct New Medium
Enterprises (NME), is based on red lasers, and claims to be capable of
reading all preceding formats. Its disks are quad-layer, with a
current capacity of 24 GB, and NME said that its process can place up
to 20 layers on one side of a disc, allowing for 100 GB capacity. NME
said that the process can also be applied to blue lasers, increasing
capacity even further. Its key focus was on markets in China, India,
Brazil, Russia, Australia and the Middle East. A new format (and
company) believed to be rising from the ashes of NME, HD Red, expected to launch a product by the end of
2009 (it did not), which has most experts in agreement that further development
of the HD-VMD format is in limbo.

High Performance Media Access Technology (HighMAT).

Panasonic, and Microsoft developed a technology that can
store, access, and retrieve digital multimedia stored on recordable optical
discs. The High Performance Media Access Technology (HighMAT) technology stores
data such as digital music, photos, and video, and specifies the way in which
devices can access this media. While HighMat is not an entirely different
format, it has the advantage of allowing users to make better use of existing
equipment without additional monetary investment.

A HighMAT data file contains additional information about the content, such
as artist name or genre in the case of music files, enabling users to manipulate
and sort content on discs more easily. HighMAT is intended to be used with CD-R
and CD-RW. The system provides support for such file types as Windows Media
Audio, MP3, JPEG, Windows Media Video, and MPEG4. Microsoft has ceased development of the technology. and the HighMAT.com
address now redirects to the Microsoft Windows Media Player site.

Magneto-Optical Technology. As the name implies, magneto-optical is a hybrid technology, combining
magnetic and optical storage methods. With MO technology, data is written with a
laser and a magnet. A laser heats a recording bit to its Curie point (the
temperature at which molecules can be realigned when subjected to a magnetic
field). Then a magnet changes the bit’s polarity.

The most recently developed MO recording technique, Light Intensity Modulation Direct Overwrite
(LIMDOW) is 50 percent faster than conventional MO methods. Normally,
three rotations (erasing, writing, and verification) are necessary to record on
an MO disc. LIMDOW enables the erasing and writing functions to occur
simultaneously, i.e., in one rotation.

In 2001, Fujitsu and Sony
introduced prototypes of new drives and discs that can hold up to 2.3 GB of data
– almost double that of then-available removable high-capacity disc. Fujitsu
introduced the new 2.3-GB format, still well below the capacity offered by DVD-R
and DVD-RW discs, but has since abandoned the products. The 2.3-GB
Magneto-Optical format are targeted for use in backing up video and other
applications that use large volumes of data. Sony’s GIGAMO drives are designed
to read and write MO disks of all capacities to ensure data stored on all
generations of MO disc remains accessible. MaxOptix (now a Techware Distribution
company) offers capacities up to 9.1 GB on 130 mm discs, and up to 1.3 GB on 90
mm discs. Sony is the last manufacturer of magneto optical discs; all
manufacturers ceased building drives in 2010..

The drawbacks of MO technology are the cost, the relative slowness of the
process, and the lack of capacity in relationship to hard drives and DVD
technologies. UDO, with its higher capacity and lower cost, has virtually
supplanted it.

Holographic Storage. Although many critics believe that holographic
storage is still years away, the technology is so promising that a number of
vendors continue to work on producing the first products. Basically,
holographic technology uses laser and crystals rather than magnetic or optical
media to store data in holograms. The selling points are a dramatic reduction
in form factor, quicker seek time, and huge capacity per hologram. More than a
million bits of data can be stored in a single hologram, and thousands of
holograms can fit within a single centimeter wafer.

Research continues with some recent developments that bring true
holographic storage closer to reality, including:

  • Holographic Media – InPhase Technologies, a spin-off from Bell
    Labs, developed working holographic media, the tapestry Media, that it
    sought to license to device manufacturers, and include it in its own
    Tapestry drive. The media provides removable, random-access, high-density,
    high-performance, holographic storage that has a 50-year archival life and
    operates in a wide range of environmental conditions. The media is capable
    of data capacities that range from 300 GB to 1.6 TB. However, in February
    2010 the company experienced financial difficulties and shut down; it was
    revived with new investors and new management, but went bankrupt in 2011,
    and its assets were acquired by startup hVault. hVault, in turn, has
    disappeared, and InPhase assets now reside with Akonia Holographics. Akonia
    has announced that it is developing second-generation holographic
    technologies to meet the demands of big data
  • Tapestry Drives – InPhase released commercial
    WORM product that include the tapestry 300r drive with 300 GB storage capacity,
    with the tapestry 800r with 800 GB, and the tapestry 1600r with 1.6 TB of
    storage on its roadmap. These drives have no disappeared from view.
  • Micro-holographic – In April 2009, GE
    announced that it had successfully demonstrated a 500 GB
    holographic disc the size of a standard DVD. It was aimed at the archive
    industry to begin with, but was to eventually target home
    markets. GE expected that players would be capable of also playing
    existing DVDs and Blu-ray discs, and would offer capacities of
    500 GB – 1 TB. However, the company has not mentioned the technology since
    2011, so it, too, may be dead. 
  • Quantum holographic storage – In early
    2009, researchers at Stanford University stored 35 bits of data
    in the quantum space around a single electron. The technology
    allows stacking of two elements in the same space, doubling

Holographic storage was also being touted by the Holographic
Versatile Disk (HVD) alliance, an industry organization that supported the
format and a technology developed by Optware called Collinear Holography. The
group included Software Architects, InPhase, Pioneer, Panasonic, Ovalrock,
Stanford University, Sony, Fujifilm, CMC Magnetics, Texas Instruments, Optware,
Toagosei, Hitachi, Toshiba, Plasmon, Pulstec, Philips, and IBM. This group
became the HVD Forum in April 2007, and has since renamed itself to the
Holographic System Development (HSD) Forum, with eighteen members. However, even
that has disappeared.

Further Out on the Timeline

Other forays into storage technologies arise on
an almost continual basis. There are several that have generated interest from
the press and from some major vendors. A few of these are:

  • IBM Millipede – IBM
    is working on micro-electrical-mechanical (MEMS) chip systems that it says
    can hold the equivalent of 25 DVDs on a chip the size of a postage stamp.
    The system is code-named Millipede because it has thousands of very fine
    silicon tips that can punch individual bit patterns onto a thin
    film of polymer. The Millipede uses the tips to create pits, or bit
    patterns, approximately 10 nanometers wide to represent the stored data. IBM
    says that the principle is similar to the older technology of data punch
    cards, but the Millipede can also erase and rewrite data. After
    several years of development, IBM has gone silent about this
    project, leading to speculation that it has been abandoned. In
    2008, Nanochip, an Intel-backed startup, began work on a flash
    memory-based system using similar technology, but it, too has
  • Nanotechnology – Although being touted
    as a replacement for memory chips in computers, nanotechnology’s carbon
    nanotubes and other nano-technologies are being researched by Intel and
    Motorola. These could be used to replace Flash memory but could also be a
    replacement for current disk technologies. This use of nanotechnology is at
    least four to five years from a commercial product. In September
    2009, researchers at Pohang University of Science and Technology
    in Korea demonstrated reading, writing and erasure of nano storage
    with an areal density of 1.03 TB per square inch without the use
    of heat (a technology challenge of long standing). In January, 2012, IBM
    researchers created what they described as the smallest possible unit of
    magnetic storage, consisting of two rows of six iron atoms on a copper nitride
    surface. Although the work was performed at temperatures approaching absolute
    zero, they believe they can create similar storage at room temperature with as
    few as 150 atoms.
  • 5D DVD – Developed in Australia, this
    technology uses multiple colors of laser to write to multiple
    layers of a DVD-like disc. Its theoretical capacity is 10 TB, and
    in 2009 developers expected devices will be ready in 5 – 10 years.
  • Phase Change Memory
    technology uses a laser to read and write data on a thin wafer of antimony and
    tellerium. A
    laser is directed to a microscopic point on a layer of the material to
    obtain a reflection. The reflection will differ, depending on whether the
    molecules at that particular point are amorphous or arranged in a crystal.
    The two types of reflections then become the ones and zeros of data.
    Intel and STMicroelectronics developed a prototype of a four
    phase version of the technology, effectively doubling capacity. In
    2008, further development was transferred to a spin-off, Numonyx,
    then owned by Intel, STM and Francisco Partners. It was acquired
    by Micron in May 2010. In April 2010, this future tech became
    reality when Samsung shipped phase-change memory modules for
    mobile devices. In June 2011, IBM announced PCM with write speeds 100 times
    faster than flash that stays reliable for millions of write cycles. It stores
    four bits of data per cell. It is expected to be available by 2016; in
    early 2014, the company demonstrated a prototype board for storage systems. In
    January 2014, Micron withdrew all PCM products from its portfolio.

[return to top of this report]

About the Author

[return to top of this report]

Lynn Greiner is Vice President, Technical Services
for a division of a multi-national corporation, and also an award-winning
computer industry journalist. She is a member of Faulkner’s Advisor Panel.

[return to top of this report]