Effects of laser-induced discrete texture parameters on optimization of head-disk-interface tribology

Laser-induced discrete bump texture results in a simplified HDI model represented by five critical parameters: the bump height H_b , bump curvature radius R_b, bump spacing L_b, the slider crown height H_w, and the lube thickness H_l . The HDI tribology performance relies upon how to select these parameters in bump texture design as well as how to measure and control them. In this paper, analysis on fundamental bump-design issues is presented. It is found that proper discrete texture design should assure bumps are in elastic-contact regime but close to the elastic-contact limit for minimum wear failure and stiction. Minimum deformation and shear stress at bump contacts are also desired for wear durability. Longitudinal bump pattern provides best glide performance among patterns with same H_b. Stiction is low within the toe-dipping lube regime where λ=H_l/H_b is below a critical value, otherwise stiction depends on all five parameters. Results from laser-texture experiments are also discussed for understanding of the discrete bump texture design