Functionalized ion-beam carbon for magnetic disks

Presently, technologies such as ion-beam deposition and plasma-enhanced chemical vapor deposition produce thin carbon overcoats (30 Å) with a high fraction of sp³ content. These hard dense overcoats exhibit good wear durability and corrosion resistance. Lubricant pickup by the head and head degradation issues are becoming critical for the low fly height head-disk interface. The physical and chemical properties of both the carbon overcoat and the lubricant, as well as their interaction affect the head degradation. Since optimal properties of the carbon vary at the lubricant and magnetic layer interfaces, an interfacial functionality approach is needed for the design of thin overcoats. Functionalized ion beam (FIB) carbon overcoat consists of a carbon layer deposited by an ion-beam process and a top thinner layer of sputtered carbon. This FIB overcoat design controls the surface properties of the hard ion-beam carbon and demonstrates improved carbon-lubricant bonding, better glide head-disk interaction, and lower head wear with good corrosion resistance performance.