112:
144:
103:/in (160 Gbit/cm). As of August 2010, drives with densities of 667 Gb/in (103.4 Gb/cm) were available commercially. In 2016 the commercially available density was at least 1,300 Gb/in (200 Gb/cm). In late 2021 the Seagate disk with the highest density was a consumer-targeted 2.5" BarraCuda. It used 1,307 Gb/in (202.6 Gb/cm) density. Other disks from the manufacturer used 1,155 Gb/in (179.0 Gb/cm) and 1,028 Gb/in (159.3 Gb/cm).
177:
Vertimag
Systems Corporation, founded by Professor Jack Judy of the University of Minnesota. As a colleague of Iwasaki, created the first perpendicular disk drives, heads and disks in 1984. 5 MB removable floppy drives were demonstrated in IBM PCs to major computer manufacturers. Vertimag went out of
164:
In the early 2000s, three important factors came together which allowed perpendicular recording to exceed the capabilities of longitudinal recording and led to commercial success. First, the development of media with an oxide-segregant exchange-break between grains. Second, the use of a thin 'cap' on
155:
This is possible because in a perpendicular arrangement the magnetic flux is guided through a magnetically soft (and relatively thick) underlayer beneath the "hard" data storage layer (considerably complicating and thickening the total disk structure). This underlayer can be thought of as part of
151:
The true picture is a bit more complex. Perpendicular recording does indeed penetrate more deeply into the magnetic storage medium, thereby allowing a closer bit spacing without losing overall bit volume. However, the main density advantage comes from the use of a magnetically "stiffer" (higher
90:
using perpendicular recording that could store 100 kB per inch (39 kB/cm). Perpendicular recording was later used by
Toshiba in 3.5" floppy disks in 1989 to permit 2.88 MB of capacity (ED or extra-high density), but they failed to succeed in the marketplace. Since about 2005, the technology has
135:
of the material. The larger the magnetic region is and the higher the magnetic coercivity of the material, the more stable the medium is. Conversely, there is a minimum stable size for a magnetic region at a given temperature and coercivity. If it is any smaller it is likely to be spontaneously
139:
The popular explanation for the advantage of perpendicular recording is that it achieves higher storage densities by aligning the poles of the magnetic elements, which represent bits, perpendicularly to the surface of the disk platter, as shown in the illustration. In this not-quite-accurate
140:
explanation, aligning the bits in this manner takes less platter area than what would have been required had they been placed longitudinally. This means cells can be placed closer together on the platter, thus increasing the number of magnetic elements that can be stored in a given area.
160:
which transects the data storage layer. Having more of the magnetic flux penetrate the data storage layer makes the write head more efficient than a longitudinal head, produces a stronger write field gradient, and thereby allows the use of the higher coercivity magnetic storage medium.
185:
began shipping its first laptop sized 2.5-inch (64 mm) hard drive using perpendicular recording technology, the
Seagate Momentus 5400.3. Seagate also announced at that time that the majority of its hard disk storage devices would utilize the new technology by the end of 2006.
123:. If the thermal energy is too high, there may be enough energy to reverse the magnetization in a region of the medium, destroying the data stored there. The energy required to reverse the magnetization of a magnetic region is the product of the size of the magnetic region and the
642:
189:
In April 2006, Seagate began shipping the first 3.5 inch perpendicular recording hard drive, the
Cheetah 15K.5, with up to 300GB storage, running at 15,000 rpm and claim to have 30% better performance than their predecessors with a
165:
the media to control the level of exchange-coupling between grains and to enhance propagation of switching through the thickness of the medium. Third, the expiration in 2005 of the patent for the trailing-shield head invented in 1985 by
201:
In April 2006, Seagate announced the
Barracuda 7200.10, a series of 3.5-inch (89 mm) HDDs utilizing perpendicular recording with a maximum capacity of 750 GB. Drives began shipping in late April 2006.
226:
announced volume production of its WD Scorpio 2.5-inch (64 mm) hard drives using WD-designed and manufactured perpendicular magnetic recording (PMR) technology to achieve 80 GB-per-platter density.
136:
de-magnetized by local thermal fluctuations. Perpendicular recording uses higher coercivity materials because the head's write field penetrates the medium more efficiently in the perpendicular geometry.
334:
S. Khizroev, M. Kryder, Y. Ikeda, K. Rubin, P. Arnett, M. Best, D. A. Thompson, "Recording heads with trackwidths suitable for 100 Gbit/in2 density, "IEEE Trans. Magn., 35 (5), 2544–6 (1999)
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656:
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announced a 2.5-inch (64 mm) hard drive of 200-GB capacity with mass production starting in August, effectively raising the standard of mobile storage capacity.
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119:
The main challenge in designing magnetic information storage media is to retain the magnetization of the medium despite thermal fluctuations caused by the
147:
Trailing shield head with granular media. This head design provides higher field gradients and more advantageous field angles for perpendicular recording.
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99:, though this estimate is constantly changing. Perpendicular recording was predicted in 2007 to allow information densities of up to around 1,000
212:. Hitachi's first laptop drive (2.5-inch) based on perpendicular recording became available in mid-2006, featuring a maximum capacity of 160 GB.
432:
841:
54:
in Japan, and first commercially implemented in 2005. The first industry-standard demonstration showing unprecedented advantage of PMR over
245:
said its new 100GB two-platter HDD is based on perpendicular magnetic recording (PMR) and was designed in the "short" 1.8-inch form factor.
335:
733:
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181:
Toshiba produced the first commercially available disk drive (1.8") using this technology in 2005. Shortly thereafter in
January 2006,
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In
December 2006 Fujitsu announced its MHX2300BT series of 2.5-inch (64 mm) hard disk drives, with capacities of 250 and 300 GB.
673:
811:
357:
290:
55:
703:
640:, Mallary, Michael L. & Das, Shyam C., "Vertical magnetic recording arrangement", issued 1992-06-02
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276:
announced the first 7,200rpm 2.0 terabyte SATA hard drive using PMR technology with choice of SATA 2 or SAS 2.0 interface.
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come into use for hard disk drives. Hard disk technology with longitudinal recording has an estimated limit of 100 to 200
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Diagram of perpendicular recording. Note how the magnetic flux travels through the second layer of the platter.
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announced the first 1-terabyte hard drive using the technology, which they then delivered in April 2007.
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548:"Magnetic Recording Media", 1.5.3 Encyclopedia of Physical Science and Technology (Third Edition), 2003
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407:"Hitachi News Release – Hitachi achieves nanotechnology milestone for quadrupling terabyte hard drive"
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169:. This head offered higher field gradients and more favorable field angles than a simple pole head.
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Sonobe, Y.; Tham, K.K.; Umezawa, T.; Takasu, C.; Dumaya, J.A.; Leo, P.Y. (2006).
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in collaboration with researchers of Data
Storage Systems Center (DSSC) – a
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795:
animation and song explaining perpendicular recording from
Hitachi Research
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238:
models utilizing perpendicular recording, offering up to 160GB capacity.
600:"Exchange coupled composite media for perpendicular magnetic recording"
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announced the first 2.0 terabyte SATA hard drive using PMR technology.
242:
231:
216:
92:
83:
756:"Hitachi gets its one terabyte Deskstar 7K1000 drives out the door"
433:"Seagate Barracuda Compute SATA 2.5" Product Manual, October 2016"
142:
110:
561:"Effect of continuous layer in CGC perpendicular recording media"
323:
100:
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announced a 1.5 terabyte SATA hard drive using PMR technology.
78:
Perpendicular recording can deliver more than three times the
670:"First Perpendicular Recording HDD – Toshiba Press Release"
696:"Briefly: Foxconn to build 1.5m MBPs; 100GB iPod drive"
310:
S.N. Piramanayagam, J. Appl. Phys. 102, 011301 (2007).
234:
extended its 2.5-inch (64 mm) lineup to include
58:(LMR) at nanoscale dimensions was made in 1998 at
798:Perpendicular Magnetic Recording (Hardcover) by
524:"2005: Perpendicular Magnetic Recording arrives"
387:. No. 70. COMPUTE! Publications. p. 23
82:of traditional longitudinal recording. In 1986,
528:Computer History Museum, Data Storage Milestone
46:. It was first proven advantageous in 1976 by
8:
152:coercivity) material as the storage medium.
95:per square inch (16 to 31 Gb/cm) due to the
66:(NSF) Engineering Research Center (ERCs) at
657:Perpendicular Magnetic Recording Technology
565:Journal of Magnetism and Magnetic Materials
490:Journal of Magnetism and Magnetic Materials
131:, which is in turn related to the magnetic
726:"Hitachi Introduces 1-Terabyte Hard Drive"
479:
477:
457:"BarraCuda 4TB, 5TB (2.5) Product Manual"
38:), is a technology for data recording on
16:Magnetic disk drive recording technology
316:
766:from the original on 17 September 2017
178:business during the PC crash of 1985.
7:
736:from the original on 12 January 2007
706:from the original on 8 December 2006
346:Merritt, Rick (26 September 2005).
676:from the original on 14 April 2009
413:from the original on 28 April 2017
14:
360:from the original on 5 April 2023
832:Heat-assisted magnetic recording
598:Victora, R.H.; Shen, X. (2005).
486:"Future hard disk drive systems"
291:Heat-assisted magnetic recording
24:perpendicular magnetic recording
56:longitudinal magnetic recording
32:conventional magnetic recording
604:IEEE Transactions on Magnetics
348:"Hard drives go perpendicular"
1:
842:Computer storage technologies
379:Bateman, Selby (March 1986).
324:https://www.dssc.ece.cmu.edu/
156:the write head, completing a
659:" white paper, HGST Nov 2007
381:"The Future of Mass Storage"
125:uniaxial anisotropy constant
297:Shingled magnetic recording
64:National Science Foundation
60:IBM Almaden Research Center
858:
585:10.1016/j.jmmm.2006.01.164
510:10.1016/j.jmmm.2008.07.027
484:Wood, Roger (March 2009).
68:Carnegie Mellon University
624:10.1109/TMAG.2005.855263
97:superparamagnetic effect
50:, then professor of the
121:superparamagnetic limit
20:Perpendicular recording
148:
116:
286:Exchange spring media
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114:
837:Japanese inventions
789:"Get Perpendicular"
616:2005ITM....41.2828V
577:2006JMMM..303..292S
502:2009JMMM..321..555W
462:. 30 September 2020
409:. 15 October 2007.
274:Seagate Technology
260:Seagate Technology
208:announced a 20 GB
183:Seagate Technology
149:
117:
762:. 25 April 2007.
610:(10): 2828–2833.
272:In February 2009
241:In December 2006
52:Tohoku University
48:Shun-ichi Iwasaki
30:), also known as
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827:Hard disk drives
800:Sakhrat Khizroev
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267:Western Digital
230:In August 2006
224:Western Digital
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173:Implementations
167:Michael Mallary
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80:storage density
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42:, particularly
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783:External links
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222:In July 2006,
215:In June 2006,
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40:magnetic media
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700:AppleInsider
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770:8 September
417:20 February
364:26 November
88:floppy disk
821:Categories
740:10 January
710:6 December
638:USRE33949E
466:29 October
304:References
210:Microdrive
194:of 73–125
133:coercivity
107:Technology
74:Advantages
44:hard disks
391:7 October
192:data rate
764:Archived
760:Engadget
734:Archived
730:PC World
704:Archived
680:16 March
674:Archived
533:10 March
411:Archived
385:COMPUTE!
358:Archived
353:EE Times
280:See also
612:Bibcode
573:Bibcode
498:Bibcode
253:Hitachi
243:Toshiba
232:Fujitsu
217:Toshiba
206:Hitachi
196:Mbyte/s
93:gigabit
70:(CMU).
810:
644:
293:(HAMR)
84:Maxell
793:Flash
460:(PDF)
441:9 May
436:(PDF)
299:(SMR)
808:ISBN
772:2017
742:2007
712:2006
682:2008
535:2024
468:2021
443:2021
419:2008
393:2018
366:2023
236:SATA
101:Gbit
22:(or
620:doi
581:doi
569:303
506:doi
494:321
36:CMR
28:PMR
823::
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802:,
791:A
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602:.
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476:^
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26:,
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368:.
129:u
127:K
34:(
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