Method and system for providing a magnetic recording transducer using an ion beam scan polishing planarization

A method for fabricating a read sensor on a substrate for a read transducer, the method comprising:

• depositing a read sensor stack including a plurality of layers on the substrate;
• depositing a hard mask layer on the read sensor stack;
• providing a photoresist mask having a photoresist mask pattern on the hard mask layer;
• transferring the photoresist mask pattern to the hard mask layer, forming a hard mask having a pattern, the pattern covering a first portion of the read sensor stack corresponding to the read sensor, covering a second portion of the read sensor stack distal from the read sensor, and exposing a third portion of the read sensor stack between the first portion and the second portion of the read sensor stack;
• ion milling the read sensor stack, thereby removing the third portion of the read sensor stack and defining the read sensor from the read sensor stack;
• depositing an insulating layer on the read sensor;
• depositing a hard bias layer after the step of depositing the insulating layer;
• providing a mask layer including a substantially flat top surface and a plurality of thicknesses, the mask layer consisting of photoresist and being aperture free;
• focused ion beam scan (FIBS) polishing the mask layer and the hard bias layer to remove a portion of the mask layer and a portion of the hard bias layer based on the plurality of thicknesses, the step of performing the FIBS polishing further including
• measuring at least a portion of the plurality of polishing across the substrate;
• scanning across the substrate while ion polishing at a polishing angle, the ion polishing being performed for a longer time for a greater polishing of the plurality of polishing such that a greater amount of at least one of the mask layer and the hard bias layer is removed for the greater polishing of the plurality of polishing, the polishing angle corresponding to a first removal rate for the mask layer and a second removal rate for the hard bias layer, the first removal rate being is substantially equal to the second removal rate;
• and
• removing a remaining portion of the hard mask after the step of performing the FIBS polishing.