Research on MEMS - based active sliders with flying height control using PZT thin films in hard disk drives

This paper describes the development of novel PZT thin films for active sliders in hard disk drives. So far, it is common that single-layered thin films are used as micro-actuators for conventional PZT thin films such as sol-gel or sputtered thin films. In this study, however, the novel composite PZT thin films are developed. The feature is that sol-gel PZT thin film is deposited on sputtered PZT thin film fabricated on Pt/Ti bottom electrode. These multilayered composite PZT thin films are found to have the higher (111) preferred orientation as well as better P-E hysteresis loop characteristics than not only sol-gel PZT thin films but also sputtered PZT thin films. Furthermore, the piezoelectric strain constant d31 for the novel PZT thin films is identified to be 189 × 10−12m/V. This value is 2.0 times higher than that for conventional PZT thin films and it is found that the novel PZT thin films have good piezoelectric properties.

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Thermo-mechanical aspects of thermal flying-height control sliders for hard disk drives

Mathematics and Mechanics of Solids ◽

10.1177/1081286510387833 ◽

2011 ◽

Vol 16 (7) ◽

pp. 694-705 ◽

Cited By ~ 1

Author(s):

Nan Liu ◽

Jinglin Zheng ◽

David B. Bogy

Keyword(s):

Hard Disk Drives ◽

Hard Disk ◽

Flying Height ◽

Disk Drives ◽

Height Control ◽

Thermal Flying Height Control

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Investigation of Head Burnishing of Thermal Flying Height Control Sliders

ASME 2013 Conference on Information Storage and Processing Systems ◽

10.1115/isps2013-2909 ◽

2013 ◽

Cited By ~ 3

Author(s):

Liane Matthes ◽

Ralf Brunner ◽

Bernhard Knigge ◽

Frank E. Talke

Keyword(s):

Thin Film ◽

Surface Roughness ◽

Hard Disk Drives ◽

Hard Disk ◽

Flying Height ◽

Disk Drives ◽

Lubricant Transfer ◽

Height Control ◽

Thermal Flying Height Control ◽

Disk Spacing

The head-disk spacing in current hard disk drives is approximately 1–2 nm. This distance is on the same order as the peak to valley surface roughness of a typical thin film disk. If one attempts to reduce the head-disk spacing even more, intermittent contacts between the slider and the disk are more likely to occur. Intermittent contacts are undesirable since they can result in slider and disk wear, lubricant transfer or degradation of the read and write elements.

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Flying Clearance Distribution With Thermal Flying Height Control in Hard Disk Drives

Journal of Tribology ◽

10.1115/1.4001024 ◽

2010 ◽

Vol 132 (2) ◽

Cited By ~ 2

Author(s):

Sung-Chang Lee ◽

George W. Tyndall ◽

Mike Suk

Keyword(s):

Temperature Compensation ◽

Hard Disk Drives ◽

Hard Disk ◽

Flying Height ◽

Disk Drives ◽

Disk Interface ◽

Height Control ◽

Thermal Flying Height Control ◽

Height Change ◽

The Individual

Flying clearance distribution with thermal flying height control (or thermomechanical actuation) is characterized. Especially, factors contributing to variation in the flying clearance are identified based on the flying height change profiles taken from the burn-in process of hard disk drives and Gage R&R (repeatability and reproducibility) test of touch down repeatability. In addition, the effect of static temperature compensation scheme on the flying clearance distribution is investigated, and the disadvantage of static adaptation to temperature change is identified. In order to avoid early catastrophic head-disk interface failures due to poor static temperature compensation, dynamic clearance adjustment is necessary whenever environmental condition changes. Otherwise, static temperature compensation using the individual temperature sensitivity values of each head needs to be applied.

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