3 GB IN(2) RECORDING DEMONSTRATION WITH DUAL ELEMENT HEADS AND THIN-FILM DISKS/

We have successfully demonstrated magnetic recording at an areal densi ty of 3 Gb/in(2) with narrow track inductive-write MR-read dual elemen t heads on low noise Co alloy thin film disks. In this demonstration, the write head is a ten turn thin film inductive head with thick and n arrow P2 pole-tips. The read head is a shielded similar to 1 mu m trac kwidth MR sensor soft-film biased in the read region for linearization and exchange-biased at the tail regions for magnetic stabilization. D uring recording tests, the heads were flown over low noise Co-alloy me dia at a clearance similar to that in the previous I Gb/in(2) recordin g experiment. Results showed good writability from the narrow track wr ite head in terms of overwrite and hard transition shift. Readback yie lds symmetrical signals as large as 600 mu V (p-p) and rolloff measure ments showed 50% densities as high as 5000 fc/mm. Track profile and mi crotrack profile measurements showed the write and read trackwidths to be similar to 1.4 mu m and similar to 1.1 mu m respectively, with tig ht side-writing and side-reading characteristics. An overall assessmen t of the parametric recording results suggested areal density feasibil ity up to as high as 3 Gb/in(2). This projection was confirmed by erro r rate performance testing using a PRML channel with a digital filter and write precompensation, At a data rate of 4-5 Mb/s and at very low ontrack error, a linear density as high as 185 Kbpi and an optimized t rack pitch as narrow as 1.5 mu m were achieved, corresponding to an ar eal recording density of similar to 3.1 Gb/in(2).