A new write head trimmed at wafer level by focused ion beam

Our new write head is trimmed using a focused ion beam (FIB) at the wafer level before depositing a protective layer of Al₂O ₃. Since this head has no hollows, no Ga implantation, and no recessions caused by the ion beam at the air bearing surface (ABS), it can achieve good write performance at very low flying height with high reliability. Our new fabrication technique also protects the Magnetoresistive (MR) sensor from exposure to the ion beam. We fabricated an inductive-write/MR-read composite head. Test results exhibited a write performance as good as that of non-trimmed wide heads, while providing a smaller erase width