Decomposition of perfluoropolyether lubricant picked up on actual air bearing surface in heat-assisted magnetic recording

The thermal decomposition of D-4OH lubricant thin film on an actual air-bearing surface under heating conditions was investigated using time-of-flight secondary ion mass spectroscopy (TOF-SIMS). The substrates used in this experiment are those of actual magnetic head sliders with diamond-like carbon (DLC) thin-film coatings. Two kinds of surfaces were prepared; an undisturbed DLC thin-film surface and an Al
₂
O
₃
surface exposed by sputtering of the DLC thin film. Comparison of the changes in the positive mass spectra due to heating confirmed that thermal decomposition of the D-4OH lubricant thin-film occurred and that it could be accelerated by the catalysis of Al
₂
O
₃
at heating temperatures below 150°C. This is despite the fact that the D-4OH lubricant thin-film on the undisturbed DLC thin-film surface did not decompose.