Cusp-Field Single-Pole-Type (CF-SPT) Head for Perpendicular Recording

Part of the Nanostructure Science and Technology book series (NST)


Maintaining the thermal stability of small magnetic grains is important for perpendicular magnetic recording; for achieving higher recording densities, it is inperative to continue to increase the strength and sharpness of the magnetic recording field of single-pole-type (SPT) heads because the anisotropy energy of the recording media becomes large, thereby threatening the thermal stability. Development of soft magnetic pole material with a high saturation magnetic flux density, B s, is the first requirement. Furthermore, improvement of the head structure is important because little room is left for the B s increasing to its practical limit of 2.45 T.

The first single-pole head was developed as an auxiliary-pole-driven-type head [1]. This head underscored the importance of the head-energizing method for realizing a strong and sharp recording field in which the coil created the strongest field at the top in the main pole located at the air-bearing surface (ABS). This concept was inherited by the thin film SPT head [2] depicted in Fig. 8.1a. In the head, the coil of the helical structure is wound closely around the main pole throat to excite the pole tip directly with the strongest coil field. As depicted in Fig. 8.1b, field calculations reveal that the highest head field was obtained when the coil recession height, h, from the ABS was zero.


Seed Layer Main Pole Stray Field Coil Field Head Field 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    Iwasaki S, Nakamura Y (1978) The magnetic field distribution of a perpendicular recording head. IEEE Trans Magn 14:436–438CrossRefGoogle Scholar
  2. 2.
    Muraoka H et al (1999) Low inductance and high efficiency single-pole writing head for perpendicular double layer recording media. IEEE Trans Magn 35:643–648CrossRefGoogle Scholar
  3. 3.
    Ise K et al (2000) High writing-sensitivity single-pole head with cusp-field coils. IEEE Trans Magn 36:2520–2523CrossRefGoogle Scholar
  4. 4.
    Brankovic SR et al (2006) Pulse Electrodeposition of 2.4 T Co37Fe63 alloys at nanoscale for magnetic recording application. IEEE Trans Magn 42:132–139CrossRefGoogle Scholar
  5. 5.
    Osaka T et al (1998) A soft magnetic CoNiFe film with high saturation magnetic flux density and low coercivity. Nature 392:796–798CrossRefGoogle Scholar
  6. 6.
    Yoshino M et al (2005) All-wet fabrication process for ULSI interconnects technologies. Electrochim Acta 51:916–920CrossRefGoogle Scholar
  7. 7.
    Yamakawa K et al (2002) A new single-pole head structure for high writability. IEEE Trans Magn 38:163–168CrossRefGoogle Scholar
  8. 8.
    Yamakawa K et al (2007) FEM model analysis of single-pole-type heads with different coil structures. IEICE Trans Electron E90-C:1555–1560CrossRefGoogle Scholar
  9. 9.
    George P et al (2003) High-frequency inductance measurements and performance projections made for cusp-field single-pole heads. IEEE Trans Magn 39:1949–1954CrossRefGoogle Scholar
  10. 10.
    Payne W, Cain A, Bauldwinson M, Hempstead R (1996) Challenges in the practical implementation of perpendicular magnetic recording. IEEE Trans Magn 32:97–102CrossRefGoogle Scholar
  11. 11.
    Nakamoto K et al (2004) Single-pole/TMR heads for 140-Gb/in2 perpendicular recording. IEEE Trans Magn 40:290–294CrossRefGoogle Scholar
  12. 12.
    Hirata K et al (2005) Material properties and domain structure influence on pole erasure occurrence in perpendicular recording heads. IEEE Trans Magn 41:2902–2904CrossRefGoogle Scholar
  13. 13.
    Hirata K, Roppongi T, Noguchi K (2005) A study of pole material properties for pole erasure suppression in perpendicular recording heads. J Magn Man Mater 287:352–356CrossRefGoogle Scholar
  14. 14.
    Gao KZ, Bertram HN (2002) 3-D micromagnetic simulation of write field rise time in perpendicular recording. IEEE Trans Magn 38:2063–2065CrossRefGoogle Scholar
  15. 15.
    Mallary ML (1987) Vertical magnetic recording arrangement. US Patent #4 656 546Google Scholar
  16. 16.
    Mallary ML, Das SC (1992) Reissued #33 949Google Scholar
  17. 17.
    Ise K, Yamakawa K, Honda N (2003) High-field gradient cusp field single-pole writing head with front return yoke. IEEE Trans Magn 39:2374–2376CrossRefGoogle Scholar
  18. 18.
    Takahashi S, Yamakawa K, Ouchi K (2001) 2 steps type of single pole head for ultra narrow track. Tech Rep IEICE MR2001-1:1-8Google Scholar
  19. 19.
    Takahashi S, Yamakawa K, Ouchi K (2002) Single-pole type head with multicharged surfaces for ultrahigh density recording. J Appl Phys 91:6839–6841CrossRefGoogle Scholar
  20. 20.
    Gao KZ, Bertram HN (2002) Write field analysis and write pole design in perpendicular recording. IEEE Trans Magn 38:3521–3527CrossRefGoogle Scholar
  21. 21.
    Ise K et al (2006) New shielded single-pole head with planar structure. IEEE Trans Magn 42:2422–2424CrossRefGoogle Scholar
  22. 22.
    Kanai Y et al (2003) Recording field analysis of narrow-track SPT head with side shields, tapered main pole, and tapered return path for 1 Tb/in2. IEEE Trans Magn 39:1955–1960CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Akita Research Institute Of Advanced Technology (AIT)ArayaJapan

Personalised recommendations