Process for making studless thin film magnetic head
AssigneeSeagate Technology LLC
InventorsUri Cohen, Gene P. Bonnie
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AssigneeSeagate Technology LLC
InventorsUri Cohen, Gene P. Bonnie
Estimating the term…
A method for pattern-etching thick alumina layers in the manufacture of thin film heads (TFH) by using compatible metallic mask layers and a dilute (1:2) HF in water etchant. The deep alumina etching facilitates a studless TFH device where the coil and bonding pads are deposited and patterned simultaneously, and vias are later etched through the alumina overcoat layer to expose the bonding pads. The method also enables the etching of scribe-line grooves of street and alleys across the wafer for sawing and machining of sliders. These grooves eliminate most alumina chipping due to stress and damage introduced by the sawing and machining operations Similarly, pattern-etching of the alumina undercoat facilitates the formation of precise craters for recessed structures. These can improve planarity and alleviate problems related to adverse topography and elevated features of TFH devices.
A process for pattern-etching an alumina layer, including the steps of:
A process of etching alumina comprising the step of exposing the alumina to an etchant comprising a mixture of HF and water, wherein the concentration of HF is in the range of 10% to 25% by weight.
Dependencies are inferred from the claim text.