Slider surface control for ultra-high density recording

Abstract

Ultra-high density magnetic recording requires very low head-media physical spacing of less than 5 nm. The surface morphologies of the slider’s air-bearing surface (ABS) and the magnetic media surface are key limiting parameters to achieve this spacing requirement and therefore need to be further improved. For slider’s ABS, further reduction in surface roughness means further optimization of the nanogrinding process. This paper presents an experimental study to reduce ABS roughness in the nanogrinding process with fine diamond abrasives that are 50 nm in size. Average roughness (R a) of approximately 0.2 and 0.3 nm was achieved for Al2O3 and AlTiC portions of the ABS, respectively. Nanogrinding process parameters, such as load and speed did not affect the minimum ABS roughness significantly. However, the load applied affected the time required to attain the minimum roughness value.