Dependence of thin film media microstructure and recording properties on composition of Cr-based very thin seedlayer

Summary form only given. Recent studies have shown that WCr seedlayer with the thickness of about 1 nm is effective to reduce both the grain size and the media noise in longitudinal media. It is considered that the very thin seedlayer forms an island-like structure which increases the nucleation sites density of the substrate surface. Since the initial growth form of the seedlayer strongly depends on the melting point of the seedlayer, it is essential to study the effect of the melting point of the seedlayer on the media properties. We study the dependence of the microstructure, magnetic and R/W properties on the melting point of very thin Cr-based seedlayer to clarify the design guidelines for media using such a kind of seedlayer. The media were deposited onto textured NiP/Al substrates. After heating the substrate up to 250/spl deg/C, deposition of 0.5 nm seedlayer, dry etching treatment with Ar gas and deposition of 10 nm CrMo/sub 15/ underlayer, 20 nm CoCr/sub 24/Pt/sub 12/B/sub 4/ magnetic layer and 7 nm C protective layer were performed successively. The melting point of the seedlayer was varied from 1600/spl deg/C to 3400/spl deg/C by using various materials such as Cr/sub 85/Ti/sub 15/, Cr, W/sub 25/Cr/sub 75/, W/sub 50/Cr/sub 50/, W/sub 75/Cr/sub 25/ and W.