High Spatial Resolutive Method Observing the Lubricant Distribution on Magnetic Recording Media

A new method to evaluate the distribution of perfluoropolyether lubricant on hard disks was developed. We used a scanning probe microscope (SPM) technique with the dynamic force mode to detect the adhesion between the tip and the lubricant layer. We found that the distribution of phase of the cantilever oscillation varied with the cantilever amplitude when hard disks were observed, and that the behavior of how the phase image varies with the cantilever amplitude gives the distribution of the lubricant. The relative lubricant amount estimated by this method was linearly correlated with the lubricant thickness measured by Fourier transform infrared spectroscopy (FT-IR). This suggested that the method could quantitatively evaluate the lubricant distribution. Visualization of the lubricant distribution showed that the lubricant was thicker at the bottoms and thinner at the bevels around grooves in the mechanical texture. [S0742-4787(00)02104-4]