LASER REMOVAL OF PARTICLES FROM MAGNETIC HEAD SLIDERS

A quantitative investigation of laser-induced removal of particles fro m magnetic head slider surfaces has been carried out. The damage thres holds of magnetic head sliders for laser fluence and pulse number were found to be about 150 mJ/cm(2) and 5000 pulses at 100 mJ/cm(2), respe ctively. For laser fluence or pulse number above the damage threshold, laser irradiation onto magnetic head slider surfaces can cause microc racks around the pole tips. It is found that laser cleaning efficiency increases with increasing laser fluence and pulse number, but does no t depend on repetition rate up to 30 Hz. Laser cleaning efficiency of removing particles from magnetic head slider surfaces can reach about 90% for Al particles and 100% for Sn particles, respectively, under ap propriate conditions without causing damage. The mechanisms of laser c leaning of particles from magnetic head slider are laser-induced surfa ce vibration, particle vibration, particle thermal expansion, and abla tion with high laser fluence, which produce forces strong enough to de tach particles from slider surfaces. Based on the above cleaning mecha nisms, the dependence of laser cleaning efficiency on laser parameters can be explained. (C) 1996 American Institute of Physics.