Functional collapse of designed surface texture for stiction prevention instorage disk drives

Laser texture is widely used to prevent stiction in the head disk interface . The stiction protection depends on the effective height of the laser text ure. The balance between the meniscus and mechanical deformation forces is described when lubricant migrates into the head disk interface. When the el astic deformation forces cannot balance the meniscus force, the laser textu re bumps collapse and the protection against stiction is lost. A critical b ump height is defined. Bump collapse is experimentally demonstrated by moni toring the capacitance between head and disk when lubricant migrates from t he trailing edge of a slider into the head disk interface. An interface wit h high bumps shows a small capacitance increase since the mechanical deform ation forces can balance the meniscus forces with only small bump compressi on. Consistent with a calculated capacitance increase under bump collapse, an interface with low bumps shows a large capacitance increase.