MEDIA TRIBOLOGY OPTIMIZATION FOR PROXIMITY RECORDING

The demand for data storage capacity has increased dramatically in rec ent years. Areal density has been increasing at a 50 to 60% annual com pound growth rate. In order to support this growth rate, especially fo r inductive recording, the magnetic spacing loss between the recording head and the disk must be reduced. The introduction of the general cl ass of ''proximity'' recording heads has provided the drive designer w ith a way to mitigate this requirement. However, because these heads a llow for continuous or at least semi-continuous head disk contact duri ng drive operation, the formula for successful mechanical performance of the head disk interface has changed. Several areas of tribology mus t be re-addressed to meet the challenges of proximity recording: textu ring must be done in a 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 i s another important area of focus to insure proper lubricant conformat ion and hydrophobic behavior of the finished media surface. The tradit ional CSS based evaluation of head/media reliability has to be augment ed by on-track flyability testing as well as seek based testing. When the tribology system is optimized, on-track flyability testing indicat es that head build-up is minimized and neither the recording performan ce nor the flyability of the head is compromised. Seek based CSS testi ng and traditional stiction/friction measurements in several environme nts further establishes the viability of the proximity recording head/ media interface.