Static and Dynamic Slider Air-Bearing Behavior in Heat-Assisted Magnetic Recording Under Thermal Flying Height Control and Laser System-Induced Protrusion

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• 作者：Joanna Bechtel Dahl (1)
  David B. Bogy (1)
  
• 关键词：Heat ; assisted magnetic recording ; Air bearing ; Simulation ; Near ; field transducer ; Thermal flying height control ; Static and dynamic response
• 刊名：Tribology Letters
• 出版年：2014
• 出版时间：April 2014
• 年：2014
• 卷：54
• 期：1
• 页码：35-50
• 全文大小：1,371 KB
• 参考文献：1. Xu, B., Li, J., Toh, Y., Ye, K., Zhang, J.: Dynamic thermal responses of heat-assisted magnetic recording head in data writing process. IEEE Trans. Magn. 48, 3280-283 (2012) CrossRef
  2. Wu, A.Q., Kubota, Y., Klemmer, T., Rausch, T., Peng, C., Peng, Y., Karns, D., Zhu, X., Ding, Y., Chang, E.K., Zhao, Y., Zhou, H., Gao, K., Thiele, J.U., Seigler, M., Ju, G., Gage, E.: HAMR areal density demonstration of 1+ Tbpsi on spinstand. In: The magnetic recording conference (TMRC) 2012. San Jose, CA, USA (2012)
  3. Challener, W., Peng, C., Itagi, A., Karns, D., Peng, W., Peng, Y., Yang, X., Zhu, X., Gokemeijer, N., Hsia, Y.T., Ju, G., Rottmayer, R., Seigler, M.: Heat-assisted magnetic recording by a near-field transducer with efficient optical energy transfer. Nat. Photonics 3, 220-24 (2009) CrossRef
  4. Budaev, B.V., Bogy, D.B.: On the lifetime of plasmonic transducers in heat assisted magnetic recording. J. Appl. Phys. 112, 034512 (2012) CrossRef
  5. Kryder, M., Gage, E., McDaniel, T., Challener, W., Rottmayer, R., Ju, G., Hsia, Y.T., Erden, M.: Heat assisted magnetic recording. Proc. IEEE 96, 1810-835 (2008) CrossRef
  6. Xu, B., Yuan, H., Zhang, J., Yang, J., Ji, R., Chong, T.: Thermal effect on slider flight height in heat assisted magnetic recording. J. Appl. Phys. 103, 07F525 (2008)
  7. Zheng, H., Li, H., Talke, F.E.: Numerical simulation of thermal flying height control sliders in heat-assisted magnetic recording. Microsyst. Technol. 18, 1731-739 (2012) CrossRef
  8. Xu, B., Chia, C.W., Zhang, Q., Toh, Y.T., An, C., Vienne, G.: Thermal analysis of heat-assisted magnetic recording optical head with laser diode on slider. Jpn. J. Appl. Phys. 50, 09MA05 (2011) CrossRef
  9. Xu, B., Toh, Y., Chia, C., Li, J., Zhang, J., Ye, K., An, C.: Relationship between near field optical transducer laser absorption and its efficiency. IEEE Trans. Magn. 48, 1789-793 (2012) CrossRef
  10. Liu, N., Bogy, D.B.: Temperature effect on a HDD slider’s flying performance at steady state. Tribol. Lett. 35, 105-12 (2009) CrossRef
  11. Zhou, W., Wong, C., Liu, B., Yu, S., Hua, W.: Effects of temperature dependent air properties on the performances of a thermal actuated slider. Tribol. Int. 42, 902-10 (2009) CrossRef
  12. Fukui, S., Kaneko, R.: Analysis of ultra-thin gas film lubrication based on linearized Boltzmann equation: first report derivation of a generalized lubrication equation including thermal creep flow. ASME J. Tribol. 110, 253-62 (1988) CrossRef
  13. Bechtel, J.E., Bogy, D.B.: Heat-assisted magnetic recording air bearing simulations that account for lateral air temperature variation. IEEE Trans. Magn. 47, 2379-382 (2011) CrossRef
  14. Stipe, B.C., Strand, T.C., Poon, C.C., Balamane, H., Boone, T.D., Katine, J.A., Li, J.L., Rawat, V., Nemoto, H., Hirotsune, A., Hellwig, O., Ruiz, R., Dobisz, E., Kercher, D.S., Robertson, N., Albrecht, T.R., Terris, B.D.: Magnetic recording at 1.5 Pb m^? using an integrated plasmonic antenna. Nat. Photonics 4, 484-88 (2010) CrossRef
  15. Seigler, M., Challener, W.A., Gage, E., Gokemeijer, N., Ju, G., Lu, B., Pelhos, K., Peng, C., Rottmayer, R., Yang, X.: Integrated heat assisted magnetic recording head: design and recording demonstration. IEEE Trans. Magn. 44, 119-24 (2008) CrossRef
  16. Cetinorgu, E., Baloulas, B., Zabeida, O., Klemberg-Sapieha, J., Martinu, L.: Mechanical and thermoelastic characteristics of optical thin films deposited by dual ion beam sputtering. Appl. Opt. 48, 4536-544 (2009) CrossRef
  17. Sone, Y.: Molecular gas dynamics: theory, techniques, and applications. Birkh?user, Boston (2007) CrossRef
  18. Liu, C., Lees, L.: Kinetic theory description of plane compressible Couette flow. In: Talbot, L. (ed.) Rarefied gas dynamics, pp. 391-28. Academic Press, New York (1961)
  19. Liu, N., Bogy, D.B.: Particle contamination on a thermal flying-height control slider. Tribol. Lett. 37, 93-7 (2010) CrossRef
  20. Cercignani, C., Lampis, M., Lorenzani, S.: Flow of a rarefied gas between parallel and almost parallel plates. In: Proceedings of 24th international symposium on rarefied gas dynamics, vol. 762, pp. 719-24. American Institute of Physics, AIP conference proceedings, Melville, NY (2005)
  21. Loyalka, S.: Thermal transpiration in a cylindrical tube. Phys. Fluids 12, 2301-305 (1969) CrossRef
  22. Kennard, E.H.: Kinetic theory of gases with an introduction to statistical mechanics. New York: McGraw-Hill (1938)
  23. White, F.M.: Fluid Mechanics, 5 edn. McGraw-Hill, New York (2003)
  24. Zhang, S., Bogy, D.B.: A heat transfer model for thermal fluctuations in a thin slider/disk air bearing. Int. J. Heat Mass Transf. 42, 1791-800 (1999) CrossRef
  25. Chen, D., Liu, N., Bogy, D.: A phenomenological heat transfer model for the molecular gas lubrication system in hard disk drives. J. Appl. Phys. 105, 084303 (2009) CrossRef
  26. Hu, Y.: Head–disk-suspension dynamics. Ph.D. thesis, University of California, Berkeley (1996)
  27. Lu, S.: Numerical simulation of slider air bearings. Ph.D. thesis, University of California, Berkeley (1997)
  28. Cox, B., Bogy, D.B.: The CML air bearing design program (CMLAir), version 7 user manual (2007)
  29. Greenwood, J., Williamson, J.: Contact of nominally flat surfaces. Proc. R Soc. Lond. 295, 300-19 (1966) CrossRef
  30. Chen, D., Bogy, D.B.: Intermolecular force and surface roughness models for air bearing simulations for sub-5?nm flying height sliders. Microsyst. Technol. 13, 1211-217 (2007) CrossRef
  31. Bhargava, P.: Numerical simulations of the head–disk interface in hard disk drives. Ph.D. thesis, University of California, Berkeley (2008)
  32. Wu, L., Bogy, D.B.: Effect of the intermolecular forces on the flying attitude of sub-5 NM flying height air bearing sliders in hard disk drives. J. Tribol. 124, 562-67 (2002) CrossRef
  33. Gupta, V., Bogy, D.B.: Dynamics of sub-5-nm air-bearing sliders in the presence of electrostatic and intermolecular forces at the head–disk interface. IEEE Trans. Magn. 41, 610-15 (2005) CrossRef
  34. Zheng, J., Bogy, D.B.: CML TFC code user’s manual (2009)
  35. Kays, W.M., Crawford, M.E.: Convective heat and mass transfer. McGraw-Hill, New York (1993)
  36. Zeng, Q.H., Bogy, D.B.: Stiffness and damping evaluation of air bearing sliders and new designs with high damping. J. Tribol. 121, 341-47 (1999) CrossRef
  
• 作者单位：Joanna Bechtel Dahl (1)
  David B. Bogy (1)
  
  1. Computer Mechanics Laboratory, Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA, 94720, USA
  
• ISSN：1573-2711

文摘

The air bearing’s response to regions of elevated temperature on its bounding surfaces (the slider and disk) may be an important consideration in the head–disk interface design of heat-assisted magnetic recording (HAMR) systems. We implement the general non-isothermal molecular gas lubrication equation into an iterative static solver and dynamic air-bearing solver to evaluate the effect of localized heating of the air-bearing surface (ABS) due to the near-field transducer (NFT). The heat-dissipating components in our simplified HAMR design are the NFT, laser diode, and thermal flying height control (TFC) heater. We investigate the effect of each HAMR slider component on ABS temperature and thermal deformation and the slider’s flying height. The NFT induces a localized thermal spot and protrusion on the larger TFC bulge, and it is the location of maximum temperature. This ABS temperature profile alters the air-bearing pressure distribution, increasing the pressure at the hot NFT location compared with predictions of an isothermal air-bearing solver, so that the center of the pressure acting on the ABS is slightly closer to the trailing edge, thereby decreasing the pitch angle and increasing the minimum flying height. Other researchers have shown that the NFT’s thermal response time may be much faster than its protrusion response time (Xu et al. in IEEE Trans Magn 48:3280-283, 2012). The slider’s dynamic response to a time-varying NFT thermal spot on the ABS while the combined TFC and NFT induced thermal protrusion remains constant is investigated with our dynamic air-bearing solver. We simulate the slider’s step response to a suddenly applied ABS temperature profile and a pulsed temperature profile that represents laser-on over data zones and laser-off over servo zones. The sudden (step) or rapid (pulse) increase in ABS temperature induces a sudden or rapid increase in pressure at the NFT location, thereby exciting the air bearing’s first pitch mode. For the slider design and simulation conditions used here, the result of the pitch mode excitation is to alter the position of the center of pressure in the slider’s length direction, thereby changing the pitch moment. In response, the pitch angle and minimum flying height change. The step response decays after approximately 0.15?ms. Because the laser duty cycle is much shorter than this response time, a periodic disturbance is predicted for the center of pressure coordinate, pitch angle, and minimum flying height. The peak-to-peak minimum flying height modulations are relatively small (only up to 0.126?nm); more significantly, the time-averaged minimum flying height increases 0.5?nm for the NFT that reached 208?°C compared to simulations of the isothermal ABS at ambient temperature.