Laser processes for precise microfabrication of magnetic disk-drive components

Abstract

The technique of laser micro-processing has recently found several important and widespread applications in the manufacturing of disk-drive components. Examples provided here include the cleaning of surface contaminants, the formation of nano-bumps on disk surfaces for controlled surface texturing or for making nanometer-height standards, and the micro-bending of magnetic head sliders for flight-height controls. Short-pulsed laser irradiation at suitable wavelength, fluence, and incidence direction can be used to clean off particulate and organic-film contaminants from surfaces of critical components, for example, the slider and the disk. Controlled disk texturing is needed to alleviate the problem of stiction which occurs when the disk stop spinning and the super-smooth slider comes into stationary contact with the super-smooth disk. A compact laser operating at high pulse repetition rate can be used to produce a low-stiction landing zone composed of typically a million nano-bumps. This can be done both for NiP/aluminum disks, or for glass disks. Single isolated bump with 3 specified height for providing height-standard can also be tailor-made. Very recently, a laser curvature adjust technique has been developed and implemented into production of magnetic head sliders. Here, microscopic adjustments of the curvature of air bearing surface of sliders can be produced by suitable laser scribing at the back side of the ceramic slider.