Optimization of Ultrathin Carbon Overcoats on Hard Disk Media

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Abstract

Reduction of the protective carbon overcoat (COC) thickness down to ≤2 nm on hard disk media is essential based on current perpendicular magnetic recording technology, in order to achieve areal densities of >1 Tb/in2. Because of its potential to achieve comparably higher sp3 carbon bonding and a denser carbon network, hence better film coverage at lower overcoat thicknesses, the filtered cathodic vacuum arc (FCVA) technique is a promising option for COC fabrication on future media. In addition, the ability to tune the energy of the incoming C+ ions is advantageous for optimizing the functional properties of the COC. In this chapter, the effects of C+ ion energy, thickness and the extent of atomic mixing on the microstructural and functional properties of ultrathin COCs are discussed, and how the FCVA process can be optimized to achieve the most desirable functional properties for the media.

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© Springer Nature Singapore Pte Ltd. 2017

Authors and Affiliations

  1. 1.Department of Electrical and Computer EngineeringNational University of SingaporeSingaporeSingapore

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