SURFACE MICROTEXTURE CHARACTERISTICS OF ALTERNATIVE SUBSTRATE THIN-FILM MEDIA AND THEIR RELATIONSHIP TO TRIBOLOGICAL PERFORMANCE

Friction- and glide-related problems have been at the root of many of the limitations to the development of high performance thin film media. Research has shown that the potential of using alternative substrates as the next generation media for small form factor and high capacity drives is very promising because of the substrates' superior tribological and glide performance. Surface topography measurements of canasite substrate thin film rigid disks with a variety of surface profiles were made with conventional non-contact optical profilometry and atomic force microscopy. The importance of the surface characteristics of different texture are discussed with respect to various roughness parameters (R(a), peak-to-valley, zero crossing, summit and bearing ratio, and micropit dimensional measurements). The relationship between friction and surface roughness during 1 rev min(-1) drag and start-stop testing was studied. The roughness parameters have been demonstrated to be well correlated with the frictional behavior at the head-disk interface. Finally, experimental results of take-off measurements and glide height performance of canasite disks with various surface roughnesses are also described.