Predicting the flying performance of thermal flying-height control sliders in hard disk drives

Liu, Nan; Zheng, Jinglin; Bogy, David B.

doi:10.1063/1.3456541

Cited by 12 publications

(9 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diameter of the laser heating area is several times the slider-disk spacing. The heat flux across the slider-disk interface has been shown to be dominated by the heat conduction between the slider and the disk at different temperatures, which can be calculated to sufficient accuracy by [31][32][33] q ¼ Àk…”

Section: Effect Of Adsorbed Water Film On Heat Transfermentioning

confidence: 99%

Adsorbed Water Film and Heat Conduction from Disk to Slider in Heat-Assisted Magnetic Recording

Zhou

et al. 2014

Tribol Lett

View full text Add to dashboard Cite

In heat-assisted magnetic recording (HAMR), a tiny area of magnetic recording media has to be heated up to a high temperature with laser to lower the coercivity temporarily for information to be written on the area. In a humid environment, some of the water vapor molecules adsorb on the disk surface to form a water film. In HAMR writing, the adsorbed water film on the disk surface will desorb instantly from the high-temperature laser heating area to become high-temperature high-pressure water vapor. The water vapor molecules will transfer extra heat from the high-temperature laser heating area on the disk surface to the slider, which makes the temperature of the slider surface higher in a humid environment than that in dry air. The heat transfer increases dramatically with relative humidity and with the decrease in slider-disk spacing.

show abstract

Section: Effect Of Adsorbed Water Film On Heat Transfermentioning

confidence: 99%

Adsorbed Water Film and Heat Conduction from Disk to Slider in Heat-Assisted Magnetic Recording

Zhou

et al. 2014

Tribol Lett

View full text Add to dashboard Cite

show abstract

“…The heat flux on the ABS has been shown to be dominated by the heat conduction between the slider and the disk at different temperatures, which can be calculated to sufficient accuracy by [17], [18] ( 2) where is the thermal conductivity of the gas, is the accommodation coefficient of the slider's ABS, is the heat capacity ratio, and are the heat capacities at constant pressure and constant volume, is the Prandtl number, and and are the temperatures of the slider and disk, respectively. The physical properties involved in (2), in addition to the mean free path and viscosity, include the thermal conductivity and heat capacities, which can be divided into two categories: the intrinsic ones including the mean free path, the viscosity and the thermal conductivity; and the extrinsic ones including the heat capacities.…”

Section: Numerical Approachmentioning

confidence: 99%

“…During the HDDs' operation, power is applied to the heater element, which induces a nonuniform temperature field near the transducer and, due to thermomechanical coupling, causes the slider's local protrusion near the transducer. This approach effectively reduces the distance between the transducer and the disk without the heavy burden of redesigning the slider's ABS [2].…”

Section: Introductionmentioning

confidence: 98%

See 1 more Smart Citation

Thermal Flying-Height Control Sliders in Air-Helium Gas Mixtures

2011

Self Cite

View full text Add to dashboard Cite

Filling hard disk drives with air-helium gas mixtures instead of pure helium can balance performance improvement, such as reduced power cost, increased capacity and improved reliability, against manufacturing cost increase. A consistent approach is proposed here to investigate the flying performance of thermal flying height control sliders flying in air-helium gas mixtures. It is found that the smallest power required for a designated flying height appears when the gas mixture is composed of about half helium and half air. The proposed numerical approach can also find application in investigating a slider's flying performance in a humid environment.Index Terms-Flyability, gas mixtures, head-disk interface (HDI), thermal flying-height control (TFC).

show abstract

“…13 Our estimates based on previous experiments 5 indicate that 0.3Շ KnՇ 9. In this letter, we quantify the influence of gas rarefaction on the lateral resolution achievable by thermocapillary patterning for cases in which the gas layer thickness approaches the molecular mean free path.…”

Section: ͑1͒mentioning

confidence: 99%

Influence of gas rarefaction on the lateral resolution achievable by thermocapillary patterning

Liu

Troian

2011

Applied Physics Letters

Self Cite

View full text Add to dashboard Cite

Molten polymer nanofilms subject to a large transverse thermal gradient can undergo a thermocapillary instability leading to the growth of nanopillar arrays on the cooler side. The array pitch can be estimated from the fastest growing wavelength from linear stability analysis. Here we quantify the influence of gas rarefaction on thermal conduction for cases in which the gas layer thickness above the film approaches dimensions of the molecular mean free path. For experimentally relevant parameters, rarefaction increases the pitch by as much as 65%, an important consideration for noncontact three-dimensional structure formation by thermocapillary lithography. © 2011 American Institute of Physics. ͓doi:10.1063/1.3551535͔Optical lithography has served as the backbone of the semiconductor industry for decades. Reduction in the source radiation wavelength, increase in lens numerical aperture, enhanced proximity correction algorithms, and improved phase shifting masks have led to the fabrication of structures as small as tens of nanometers. While a few methods can compete with this technological achievement, there is nonetheless emerging interest in developing alternative lithographic techniques compatible not only with silicon or other semiconducting materials but also polymers, colloids, and microstructured materials.1 This pursuit is being driven by lower estimates of manufacturing costs from a fewer processing steps as well as the possibility of noncontact patterning methods based on fluid instabilities for producing threedimensional ͑3D͒ structures in a single step. It is well known that interfacial instabilities in thin films can generate periodic deformations whose amplitude and growth are typically suppressed by gravitational leveling.2 At nanoscale dimensions, however, gravitational forces are negligible in comparison to driving forces for shaping liquid structures by modulation of interfacial stresses.3 In this limit, elongated structures become possible, paving the way for fabrication techniques based on interface sculpting. As an added bonus, fluid based techniques tend to produce ultrasmooth surfaces ideally suited to photonic applications since the final structures are obtained directly from in situ solidification of molten shapes.During the past several years, 3D structure formation in nanoscale polymer melts subject to a large thermal gradient has been reported by several groups. Three growth mechanisms have been proposed including radiation pressure from interface reflection of low frequency acoustic phonons, 4,5 image charge induced electrostatic attraction between the film and target substrate, 6 and thermocapillary flow directed toward the cooler target.7 Recent hydrodynamic studies 7,8 suggest that a thermocapillary instability is the predominant driving force and that the phenomenon is basic to any viscous nanofilm not just polymer based films. 7,8 Fluid elongations are caused by a long wavelength Bénard-Marangoni instability in the limit of zero gravity. The wavelength of the fastest growing mode...

show abstract

Predicting the flying performance of thermal flying-height control sliders in hard disk drives

Cited by 12 publications

References 13 publications

Adsorbed Water Film and Heat Conduction from Disk to Slider in Heat-Assisted Magnetic Recording

Adsorbed Water Film and Heat Conduction from Disk to Slider in Heat-Assisted Magnetic Recording

Thermal Flying-Height Control Sliders in Air-Helium Gas Mixtures

Influence of gas rarefaction on the lateral resolution achievable by thermocapillary patterning

Contact Info

Product

Resources

About