Ion-induced volatilization (IIV): A method for quantitative measurement of the amounts of perfluoropolyether lubricant on a particulate disk surface and in the media porosity

A method has been developed which allows the quantitative determination of the amounts of perfluoropolyether lubricant on the top surface and in the bulk porosity of particulate disks used in magnetic storage technology. The method, ion-induced volatilization (IIV), involves subjecting a well-defined area of the lubricated disk surface to a low flux of energetic rare gas ions and monitoring the resulting partial pressure increase (at mass 69) with a quadrupole mass spectrometer. Quantification is achieved by calibrating with lubricated quartz crystal microbalances. The method is generally applicable for any lubricated surface but is specific to perfluoropolyether lubricants which undergo essentially residue-free degradation into volatile products when subjected to energetic particle bombardment.