Effect of very thin Cr-based seedlayer material with different affinity for oxygen on thin film media microstructure and recording properties

Abstract

To reduce the grain size and the media noise in longitudinal media, a sputtering process which includes the exposure of oxygen onto the surface of Cr-based seedlayers (CrTi15, Cr100, WCr75, WCr50, WCr25, and W100) with the thickness of 0.5 nm have been utilized. It is found that to effectively reduce the media grain size and improve the media signal-to-noise ratio, it is essential to utilize a very thin Cr-based seedlayer with a high melting point, a high affinity for oxygen, and which forms an island-like structure. A physical guideline for seedlayer material that is effective in reducing the grain size and the media noise is proposed.