Media tribology optimization for proximity recording

The demand for data storage capacity has increased dramatically in recent years. Areal density has been increasing at a 50 to 60% annual compound growth rate. In order to support this growth rate, especially for inductive recording, the magnetic spacing loss between the recording head and the disk must be reduced. The introduction of the general class of “proximity” recording heads has provided the drive designer with a way to mitigate this requirement. However, because these heads allow for continuous or at least semi-continuous head disk contact during drive operation, the formula for successful mechanical performance of the head disk interface has changed. Several areas of tribology must be re-addressed to meet the challenges of proximity recording: texturing must be done in manner which minimizes variation in head/media spacing; the durability and wear resistance of the disk overcoat must be optimized and lubricants with high thermal stability and resistance to catalytic breakdown must be used. The lubrication process itself is another important area of focus to insure proper lubricant conformation and hydrophobic behavior of the finished media surface. The traditional CSS based evaluation of head/media reliability has to be augmented by on-track flyability testing as well as seek based testing. When the tribology system is optimized, on-track flyability testing indicates that head build-up is minimized and neither the recording performance nor the flyability of the head is compromised. Seek based CSS testing and traditional stiction/friction measurements in several environments further establishes the viability of the proximity recording head/media interface