Supersmooth surface for low glide avalanche and low signal modulation media

This study investigates the effect of surface morphology and roughness on glide avalanche and signal amplitude modulation. Low glide avalanche and low signal modulation are obtained by the use of diamond or alumina texturing process. Diamond texturing process uses fine and tightly distributed diamond particles together with a microfiber texturing tape. The alumina texturing process which adds small amount of chemical agent in the alumina slurry can further reduce Ra to be <3 A with good uniformity. This novel alumina texturing process is found to exhibit higher stock removal rate, lower surface roughness and higher surface uniformity than that of diamond or alumina texturing process without chemical agent. The effect of these texturing processes on magnetic orientation ratio and amplitude modulation is discussed.