10 Gbit/in.(2) longitudinal media on a glass substrate (invited)

This article reports on the properties of the media prepared on glass subst rates which were used in IBM's 10 Gbit/in.(2) demonstration. In order to su pport a linear density of 315 kbpi and a track density of 33 ktpi, the rema nant coercivity H-cr and remanant moment thickness product M(r)t of the mag netic layer were 3450 Oe and 0.37 memu/cm(2), respectively. The media used a NiAl seed layer, a CrV underlayer, a Co alloy magnetic layer, and a carbo n overcoat protection layer. The magnetic film had a grain size of 12 nm as observed by transmission electron microscopy. The preferred orientation (P O) of the magnetic layer was (10 (1) over bar 0). This PO enables one to su stain high coercivities at low values of M(r)t. It is observed that the c-a xis in-plane texture of the magnetic layer is critical to achieve a low noi se medium. Using a focused-ion-beam (FIB) trimmed giant magnetoresistance h ead and conventional partial response maximum likelihood channel, the on-tr ack-error rates were measured at the 10(-10) level. (C) 1999 American Insti tute of Physics. [S0021-8979(99)60408-X].