ALLIANCES FORMED IN NANOTRIBOLOGY FOR MAGNETIC DATA STORAGE TECHNOLOGY.

As the spacing (distance from the head to the middle of the magnetic layer) in magnetic hard disk storage systems decreases in order to increase the data storage density, head disk collisions become inevitable. Friction at the interface at the time of these collisions often controls the extent of damage to the disk. The measurement of friction and wear (nanotribology) of the head disk interface requires the development of new test procedures.

NIST has signed research agreements with the University of California at San Diego (UCSD) and Data Storage Institute in Singapore, and a cooperative research agreement with a private company. These research alliances provide additional equipment, instrumentation, and expertise to allow NIST to achieve program objectives.

UCSD is providing the expertise and equipment in measuring contact forces at a head disk interface. UCSD also has extensive experience in conducting long-term durability simulation of disk coatings. The Data Storage Institute has commercial scale equipment housed in a clean room environment for film thickness measurement, micro-buffing, micro-polishing instrumentation of disks. The private company has donated research equipment and support for postdoctoral fellows to explore the fundamentals of how a surface can be protected by a monomolecular layer in the face of increasingly severe impacts.

Working with these partners, NIST researchers have developed the fundamental guidelines of how a monolayer film should be designed to achieve a certain level of shear resistance. Molecular weight, surface mobility, surface bonding characteristics have been shown to be important. Mixed molecular assemblies at a nanometer level have been shown to be feasible by controlling the deposition and surface reaction steps sequentially. This knowledge paves the way for using such monolayers to control surface properties of materials in micromechanical systems, sensors, and actuators.