4 Gbit/in.2 inductive write heads using high moment FeAlN poles

Abstract

Thin film inductive write heads incorporating 2-μm-thick single and multilayer FeAlN/SiO2 poles were fabricated. The poles were trimmed to 1 μm trackwidth using focused ion beam etching from the air bearing surface of the sliders. Tests on 2950 Oe media show satisfactory media saturation. Overwrite in excess of −43 dB and hard transition peak shift <2 nm were measured for wide trackwidth heads with 0.2 μm gap lengths. Tracks written using a 1 μm track width head were imaged using magnetic force microscopy, showing well defined transitions at linear densities up to 6600 flux changes per millimeter. A written track width of approximately 1.1 μm and a side erase band of less than 0.1 μm were observed. Assuming a coding scheme with a density ratio of 1.33, these heads promise a recording density of over 4 Gbit/in.2